Optical disc for coordinating the use of special reproduction functions and a reproduction device for the optical disc

ABSTRACT

A multimedia optical disc includes a lot of blocks each of which stores moving picture data, audio data, sub-picture data, and control information. Each piece of moving picture data, audio data, sub-picture data, and control information in the same block has the same reproduction time limit. Each piece of control information includes a mask flag indicating whether to mask a key interrupt requesting a special reproduction such as fast forward, the key interrupt being generated by the user by pressing a key on a remote controller and the like. The mask flag is effective for the key interrupt generated during the reproduction time limit stored in the control information.

This is a division of prior application Ser. No. 08/699,426, filed onAug. 19, 1996 now U.S. Pat. No. 5,923,627.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an optical disc which stores aninformation signal and a reproduction device for such a disc. Morespecifically, the present invention relates to an optical disc whichstores multimedia data including digital video data, audio data andsub-picture data as well as to a reproduction device for the disc.

2. Description of the Related Art

First Conventional Technique

Optical discs and the like have become an essential medium for thecirculation and sale of music and video software. Users can enjoy thestored content of such recording media by purchasing discs at recordshops and other retail outlets. In the present market, laser discs arewidely used as the recording medium for image software while CDs(Compact Discs) are used as the recording medium for music software.

When optical discs are used as the storage media for image software,images are recorded onto a spiral track formed on the surface of thedisc starting in the center and leading out towards the edge. By havingimages recorded in this way, the standard reproduction direction is thedirection where following the spiral track results in movement from theinner periphery of the disc to the outer periphery, while the reversereproduction direction is the direction where following the spiral trackresults in movement from the outer periphery of the disc to the innerperiphery. The information recorded on the disc is read by rotating thedisc in the standard reproduction direction and shining a laser beamonto the disc. In addition to the reproduction of the recordedinformation, other special kinds of reproduction such as “fast forwardreproduction” and “rewind reproduction” can be performed. Here, “fastforward reproduction” refers to reproduction in the standardreproduction direction which skips a certain number of units of therecorded information on the spiral track. “Rewind reproduction”,meanwhile, refers to reproduction in the reverse reproduction directionwhich skips a certain number of units of the recorded information on thespiral track.

Once a user specifies fast forward reproduction, the optical pickupreads the recorded information from the spiral track in the standardreproduction direction while skipping a fixed amount of recordedinformation. On the other hand, once the user specifies rewindreproduction, the optical pickup reads the recorded information from thespiral track in the reverse reproduction direction while skipping afixed amount of recorded information.

When the user is not interested in the output information, it ispossible for the user to view such information in a short time byspecifying fast forward reproduction. Conversely, by specifying rewindreproduction, a user gets another chance to view any data which they mayhave missed.

However, the kind of fast forward reproduction described above createsgreat problems for the developers of certain types of title. This isbecause the use of such reproduction can result in the user not viewingcommercials inserted into movies recorded onto the optical disc.

In the field of image software, there is intense price competition.Since certain kinds of software titles, such as travel “mooks” (magazinebooks) or sales promotion titles, cannot achieve the high sales achievedby hit movies, the developers of such kinds of titles end up having tooffer such titles at a low price or even provide them free. As a result,the developers of such titles often look to hotels, tour companies orairlines to sponsor the titles and so are forced to insert commercialsfor such sponsors into the images recorded on the title. However, evenif the developer can find such sponsors and insert their commercialsinto the title, it is easy for the user to miss such commercials due tothe use of fast forward reproduction.

Also, aside from commercial images, there are other images for which theviewing and understanding of the user are especially important to thetitle developer. For the example of a travel mook, such information maybe travel regulations, behavioral standards of the destination,emergency contact numbers, or advice for how to cope with crime oraccidents. Similarly, it may be necessary to properly inform the user ofinformation in the image title which, if mistaken, could cause a lot oftrouble, such as departure date, cost, cancellation regulations and thelike. Despite the need to inform the user of this information, a user ofa conventional system can, by specifying fast forward reproductioncontrary to the wishes of the developer, all too easily skip such imagecontent.

Second Conventional Technique

It would be no exaggeration to say that fast forward reproduction andrewind reproduction are “classic” reproduction functions for opticaldiscs. In recent years, the tendency of image software is for increasedinteraction, with interactive software being expected to become thenorm. Here, a first substrate technique for interactive software isdistributed recording. This refers not to the simple recording of anhour-long image onto the spiral track sequentially, but to the divisionof the image into ten or twenty-minute blocks which are recorded in anon-sequential order on a plurality of arcs of the track. A secondsubstrate technique for interactive software is random reproductionwhere image information which is divided into a plurality of blocks isreproduced in a selected order according to several sets of controldata. Such control data for random reproduction is composed of pairs ofn retrieval order of the divided-up image blocks and address informationspecifying the arcs on the spiral track where the desired images arerecorded. This control data can include several different combinationsof retrieval orders, one of which is selected by the user and thenreproduced. Once reproduction according to one set of control data iscomplete, the disc player provides the user with a display of severalbranch addresses for image reproduction using a menu or the like. Oncethe user has selected one of these branch addresses, the correspondingpiece of control data is retrieved out of all of the control data and isused for image retrieval. By repeating this operation many times,switching can be achieved between a number of reproduction routes inaccordance with the selections made by the user in response to the menu.

By using the first and second substrate techniques described above,interactive software for detective stories where the story can developin a number of ways can be achieved.

It also becomes possible to achieve interactive image software such asgoods catalogues, travel mooks, English conversation teaching materialsor the like.

For the example of a travel mook, image information for a number ofhotels, tourist spots, restaurants and sports facilities for, say,surfing or diving can be recorded on an optical disc. Here, byindicating their budget, interests and the like, a user can have imageinformation for hotels and sports displayed in accordance with theirindications.

However, if during the reproduction of the above example of interactivesoftware, the user makes use of the classic fast forward reproductionfunction, there is a second problem in that the true value of theinteractive software can be lost.

Again for the example of interactive software for a travel mook, supposethat reproduction routes in the shape of a tree with many branches areprovided in addition to direct reproduction routes with no branches. Insuch a situation, the former reproduction routes are displayed to theuser as a variety of courses using menus and so are highly interactivereproduction routes whose branch addresses are determined according touser confirmation operations. The latter reproduction routes arereproduction routes for digests which are made up of extracts of themost impressive material or material most likely to arouse the viewer'sinterest.

The tree-like reproduction routes are determined by user selection.Here, a male tour conductor can be displayed on the screen to explainimmigration procedures or any other difficult matters. Should the userbe disinterested in such an explanation, they will specify fast forwardreproduction. Such fast forward reproduction soon terminates the tourconductor's explanation so that a course selection menu for “Citycourse” or “Beach course” appears on the screen. This menu displaycontinues until a user selection is made, so that the reproduction doesnot advance. Since the user has skipped the tour conductor'sexplanation, the user will not understand the content of the courses andwill not be able to decide which course to select. Accordingly, the userwill end up rewinding to the tour conductor's explanation and, havingproperly listened to the explanation, make their selection. On selectingthe “City course”, actual footage which shows discount retail outletsfor women's jewelry and cosmetics is shown. On showing no interest insuch content, the user again specifies fast forward reproduction. Suchfast forward reproduction soon terminates the shopping guide so that acourse selection menu for “Budget course” or “Gourmet course” isdisplayed on the screen. Here, had the user viewed the preceding images,the user would be sure to readily understand what is meant by the items“Budget course” and “Gourmet course”, since this is the way in whichtravel mooks are edited by the title developer. However, by making fastforward reproduction operations after seeing only the openinginformation of a topic, the user can end up missing the explanation ofsuch courses. As before, in order to make a correct selection from themenu, the user will end up rewinding to the footage of the discountretail outlets to hear the explanation.

Such use of fast forward when viewing interactive software ends upnecessitating a troublesome rewind operation every time a menu isdisplayed, so that the user will end up hesitating before making a fastforward operation. Here, suppose that the user selects “Digest” the nexttime. This digest is a collection of the most impressive material ormaterial most likely to arouse the viewer's interest, with there beingno harm in the user fast forwarding through its content. However, afterexperiencing the trouble of having to rewind every time a fast forwardoperation was made when viewing the branch routes, the user will end uphesitating before making a fast forward operation. Here, even if thisdigest includes a shopping guide which introduces discount retailoutlets of women's jewelry and cosmetics or other such material whichthe user has already seen, the user will still end up perseveringthrough such content without fast forwarding.

For the situation described above, it is clear that the user should feelfree to fast forward through the digest image route which contains nobranches and that the user should not skip through reproduction routeswhich contain many branches. On performing such skip reproduction, theuser ends up having to terminate the skip reproduction whenever there isa menu and make a rewind operation to hear the explanation of theselection items in the menu. This kind of reproduction is highlyinefficient.

In order to overcome such a situation, it may be better to have anautomatic selection of a branch address when the user has skipreproduction performed. By doing so, since the tour conductor'sexplanation and the menu can be instantaneously reproduced, the user caneasily make a menu selection. However, by advancing to the next courseby means of such fast forward reproduction, it becomes difficult to knowwhere a current reproduction position is in the entire construction ofthe route. Here, if a variety of scenes are displayed on the screen, itbecomes difficult for the user to grasp what a present scene is, howthis scene was arrived at, or at what position in the reproduction routea user is presently situated.

From the point of view of the title developer, if such skip reproductionis achieved through automatic branches, the developer will end upputting all of their energy into the development of the story byfocusing on the position of the menus and branches, which means that thedeveloper may not get the proper message across to the user. By settingsuch automatic branches, the title developer can end up losing sight oftheir original intentions for the software title.

SUMMARY OF THE INVENTION

In view of the stated problems, it is a primary object of the presentinvention to provide an optical disc and reproduction device which willdefinitely display to the user information, such as commercials,regulations and contracts, which is regarded as important by the titledeveloper.

It is a second object of the present invention to provide an opticaldisc and reproduction device which, while preventing the execution ofspecial reproduction functions when it would destroy the value of theinteractive software, still enables a user to make valid use of suchspecial reproduction functions.

The first object of the present invention can be achieved by amultimedia optical disc comprising a data area including an objectrecording area which includes a plurality of sub-areas, wherein each ofthe plurality of sub-areas stores a plurality of blocks each of whichincludes moving picture data and management information, wherein themanagement information of each block is effective in a reproductionapparatus during an effective time, the effective time being a timeperiod during which the moving picture data in the same block as themanagement information is reproduced, wherein the management informationof each block includes user operation limitation information indicatingwhether user operations are limited during the effective time.

By means of the stated construction, management information which isonly valid during the reproduction period of the video data in the blockin the object is provided. User operation limitation information isprovided in this management information and stipulates whether specialreproduction features such as fast forward or rewind are permitted, sothat during the reproduction of images such as commercials, travelcontracts and the like, fast forward operations can be prohibited, whilesuch fast forward operations can be permitted for sections of video datawhich do not contain such essential content. By doing so, the activationof interruption processing for such special reproduction dynamicallyswitches between being permitted and being prohibited depending on thecontent of the video data.

Here, each of the plurality of sub-areas may extend over a plurality ofconsecutive sectors.

The plurality of sub-areas may be aligned in a rotation direction of themultimedia optical disc in an order whose moving picture data isreproduced.

Each piece of the management information and each piece of movingpicture data may be recorded in a sector.

The second object of the present invention can be achieved by amultimedia optical disc comprising a data area and an index area, thedata area comprising an object recording area which stores at least anobject and includes a plurality of sub-areas, wherein each of theplurality of sub-areas stores a plurality of blocks each of whichincludes moving picture data and management information, and the indexarea comprising a first index area for storing a plurality of pieces ofroute information each of which includes a sequence of addresses ofobjects; wherein alignments of the sequence of addresses of objects inthe plurality pieces of route information represent the plurality ofreproduction orders, and a second index area for storing a plurality ofpieces of user operation limitation information which respectivelycorrespond to the plurality of pieces of route information, wherein eachof the plurality of pieces of user operation limitation information setsa limit to user operations, wherein each piece of user operationlimitation information is effective during a reproduction of objectsspecified by the alignments of the sequence of addresses (hereinafterobjects specified by an alignment of the sequence of addresses arecalled a chain).

By means of the construction described above, for ten or twenty-minuteperiods during which a group of objects specified by a list of addressesare reproduced, the user can manipulate a remote controller and so givea signal for a key interrupt for special reproduction. The determinationof whether the interrupt processing for this special reproduction ispermitted or not is then made based on the user operation limitationinformation which corresponds to this list of addresses. Here, bysetting the user operation limitation information so that the activationof interrupt processing for special reproduction is prohibited for routeinformation for highly interactive reproduction routes whose branchaddresses are interactively selected by users, the activation of keyinterrupts for special reproduction, such as rewind and fast forward,made by a user who is ignorant of the highly interactive nature of thecontent can be prohibited. By prohibiting the activation of keyinterrupts for special reproduction for highly interactive reproductionroutes which contain interactive branches, execution of specialreproduction which would damage the interactive nature of a title can beprevented.

On the other hand, route information for reproduction routes which havean image content to be viewed consecutively, such as a digest version,can be set so that its user operation limitation information permits theexecution of interrupt processing for special reproduction. By doing so,when a user depresses a key, interrupt processing for specialreproduction, such as rewind and fast forward, can be activated. Byallowing the activation of key interrupt processing for specialreproduction in such reproduction routes which are designed to be viewedaccording to the user's wishes, the reproduction routes for such videodigests can be viewed using such special reproduction. Accordingly, thebenefits of such special reproduction can be achieved for thereproduction routes for such video digests.

Here, multiplexed several pieces of moving picture data, each of whichincludes an angle identifier, may be recorded in a certain area of theobject recording area, wherein the management information of the certainarea may include addresses of the multiplexed several pieces of movingpicture data, wherein each piece of the user operation limitationinformation may include a mask flag indicating whether to mask a keyinterrupt of an angle identifier change when a key is pressed to requestthe key interrupt.

By means of the stated construction, on the one hand first managementinformation provides information for the switching of the address of theoptical pickup, while on the other hand the second managementinformation includes user operation limitation information which preventthe activation of interrupt processing for key interrupts made by theuser. By doing so, while providing objects with a control mechanism forspecial reproduction, a second control mechanism can be achieved for thereproduction device which can prevent such activation from thereproduction route side. By setting the user operation limitationinformation on the reproduction route side in such a two-sided controlmechanism, the title developer is free to pass the object side controlto a desired level over to the user. By making such settings,reproduction routes which can fully achieve interaction, as well as“demonstration” reproduction routes where an interactive control contentmay partially or entirely achieved can be recorded on the same opticaldisc so that depending on the manner of the reproduction of the disc, adesired switching between these kinds of reproduction routes can beachieved.

Here, at least one block in the object recording area may include any ofmoving picture data and sub-picture data for illustrating a menuincluding a plurality of items which visually presents contents of aninteractive control, wherein the management information of said blockmay include cursor operation information for switching an item to afirst display state based on a cursor key operation made by the user,determination operation information for identifying for switching anitem to a second display state based on a determination key operationmade by the user, and a plurality of commands each of which specifies aninteractive control corresponding to an item determined by thedetermination operation, wherein each of the plurality pieces of useroperation limitation information may include a mask flag indicatingwhether to mask a key interrupt of the interactive control when the userrequests the key interrupt by using any of the cursor key operation anddetermination operation.

By means of the stated construction, while on the one hand informationfor receiving cursor operations and confirmation operations is providedin the management information, on the other hand the activation ofinterrupt processing for key interrupts by the user can be prevented byuser operation limitation information provided in the second managementinformation. By doing so, even though a control mechanism for cursoroperations and confirmation operations is provided on the object side, asecond control mechanism for preventing the activation of suchoperations is provided to the reproduction route side. By setting theuser operation limitation information on the reproduction route side insuch a two-sided control mechanism, the title developer is free to passthe object side control to a desired level over to the user. By makingsuch settings, reproduction routes which can fully achieve interaction,as well as “demonstration” reproduction routes where an interactivecontrol content may partially or entirely be achieved can be recorded onthe same optical disc so that depending on the manner of thereproduction of the disc, a desired switching between these kinds ofreproduction routes can be achieved.

Here, at least one block may include at least one of a plurality piecesof audio data and a plurality pieces of sub-picture data, wherein eachpiece of audio data and each piece of sub-picture data may specify achannel identifier, wherein the mask flag may indicate whether to mask akey interrupt of a channel change for one of audio data and sub-picturedata when a key is pressed to request the key interrupt.

By means of the stated construction, whilst providing a plurality ofchannels for the audio data and sub-picture data, the user operationlimitation information in the second management information can preventthe activation of interrupt processing for the switching of suchchannels according to a key interrupt made be a user operation. In thisway, a two-sided control mechanism is achieved whereby even when achannel switching mechanism is provided on the object side, theactivation of such an operation can be prevented on the reproductionroute side. By setting the user operation limitation information on thereproduction route side in such a two-sided control mechanism, the titledeveloper is free to pass the object side control to a desired levelover to the user. By making such settings, reproduction routes which canfully achieve interaction, as well as “demonstration” reproductionroutes where an interactive control content may partially or entirelyachieved can be recorded on a same optical disc so that depending on themanner of the reproduction of the disc, a desired switching betweenthese kinds of reproduction routes can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, advantages and features of the invention willbecome apparent from the following description taken in conjunction withthe accompanying drawings which illustrate a specific embodiment of theinvention. In the drawings:

FIG. 1A shows the appearance of the optical disc used in the presentembodiment;

FIG. 1B shows a cross-section of the optical disc;

FIG. 1C shows an enlargement of the part where the laser beam isincident on the disc;

FIG. 1D shows a row of pits in the information layer 109;

FIG. 2A shows the track arrangement of the information layer 109 of theoptical disc;

FIG. 2B shows the physical sectors of the information layer 109 of theoptical disc;

FIG. 3A shows the logical construction of the optical disc;

FIG. 3B shows the file area of the optical disc;

FIG. 3C shows the logical blocks in the volume area;

FIG. 3D and FIG. 3E show the file area;

FIG. 3F shows the Video Manager and the Video Title Sets;

FIG. 4 shows the data construction of the Video Title Set;

FIG. 5A shows the interrelations between the image material, the audiomaterial and the subtitle material and each pack in the video objects(VOB);

FIG. 5B is an expansion of the video 1 of VOBU #1;

FIG. 5C is an expansion of the video A-1 of VOBU #1;

FIG. 5D is an expansion of the SP A-2 of VOBU #2;

FIG. 6A shows the internal construction of each video pack;

FIG. 6B shows the internal construction of each audio pack;

FIG. 6C shows the internal construction of each sub-picture pack;

FIG. 6D shows the internal construction of each pack of managementinformation;

FIG. 7 shows one example of a menu;

FIG. 8 shows the internal construction of a DSI;

FIG. 9A shows the internal construction of the PCI user operationlimitation information;

FIG. 9B shows the internal construction of the Highlight Information;

FIG. 9C shows the internal construction of the PCI Standard Information;

FIG. 10A shows the content of a VOB in which Video Title Set V1 isrecorded;

FIG. 10B shows the content of a VOB in which Video Title Set V1 isrecorded;

FIG. 10C shows the content of a VOB in which Video Title Set V1 isrecorded;

FIG. 11 shows the internal construction of the Video Title Setmanagement information;

FIG. 12 shows the data construction of the PGC information;

FIG. 13 shows the content of each set of Video Title Set managementinformation in the Video Title Set V1;

FIG. 14 shows a perspective view of the reproduction device of thepresent embodiment;

FIG. 15 shows a block diagram of the internal construction of the DVDplayer 1 of the present embodiment;

FIG. 16 shows a block diagram of the construction of the system decoder86;

FIG. 17 shows the construction of the system control unit 93;

FIG. 18 shows the panel composition of the remote controller 91;

FIG. 19A shows the main flowchart for the processing by the systemcontrol unit 93;

FIG. 19B shows the main flowchart for the processing by the systemcontrol unit 93 when there is a branch;

FIG. 19C shows the main flowchart for the processing by the systemcontrol unit 93 when there is a branch;

FIG. 20 shows a flowchart for the processing by the system control unit93 based on the PGC information;

FIG. 21A shows a flowchart for the key interrupt type determinationprocess;

FIG. 21B shows a flowchart for the key interrupt type determinationprocess;

FIG. 22 shows a flowchart for the interrupt processing when either ofthe fast forward or rewind keys has been depressed;

FIG. 23 shows a flowchart for the interrupt processing when either ofthe audio or sub-picture keys has been depressed;

FIG. 24 shows a flowchart for the interrupt processing when the anglekey has been depressed;

FIG. 25 shows a flowchart for the interrupt processing when the pausekey has been depressed;

FIG. 26 shows a flowchart for the interrupt processing when either ofthe volume menu or route menu keys has been depressed;

FIG. 27 shows a flowchart for the interrupt processing when any of theNext PG, Previous PG or Top PG keys has been depressed;

FIG. 28 shows the display of a commercial on the screen of a TV monitor;

FIG. 29 shows the display of a beach scene on the screen of a TVmonitor;

FIG. 30 shows the display of a diving scene on the screen of a TVmonitor;

FIGS. 31A and 31B show the entire construction of the reproduction routeformed by Video Title Set V1;

FIG. 32 shows the internal composition of the Video Manager;

FIG. 33 shows an example of a volume menu;

FIG. 34 shows the entire construction of the reproduction route of anautomatic demo formed by Video Title Set V1; and

FIG. 35 shows the setting of the PGC user operation limitation operationfor the automatic demo.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Digital video discs (hereinafter abbreviated to DVD) which can achieve astorage capacity of 4.7 GB on one side of a 120 mm diameter optical discare well-suited for use as the multimedia optical disc in the presentembodiment.

In order to assist the reader's understanding, the following explanationhas been divided into items which, as shown below, have each been givena classification number. Here, the number of digits in theclassification number indicates the level of the item in question in theoverall structure of the explanation. Here, the highest-rankedclassification numbers are (1) and (2), with (1) relating to the opticaldisc and (2) relating to the reproduction device (disc player).

(1) Physical Construction of the Optical Disc

(1.1) Logical Construction of the Optical Disc

(1.1.1) Logical Construction . . . Video Title Set

(1.1.1.1) Video Title Set . . . Video Object (VOB)

(1.1.1.1.1) Video Object (VOB) . . . Video Pack

(1.1.1.1.2) Video Object (VOB) . . . Audio Pack

(1.1.1.1.3) Video Object (VOB) . . . Sub-Picture Pack

(1.1.1.1.4) Video Object (VOB) . . . Management Information Pack

(1.1.1.1.4.1) Management Information Pack . . . DSI Packet

(1.1.1.1.4.2) Management Information Pack . . . PCI Packet

(1.1.1.1.4.2.1) PCI Packet—PCI Standard Information

(1.1.1.1.4.2.2) PCI Packet—Highlight Information

(1.1.1.1.4.2.2.1) Highlight Information —Item Color Information

(1.1.1.1.4.2.2.2) Highlight Information—Item Information

(1.1.1.1.4.2.2.3) Highlight Information —Highlight Standard Information

(1.1.1.2) Video Title Set Management Information

(1.1.1.2.1) Video Title Set Management Information —PGC information

(1.1.2) Logical Construction-Video Manager

(2.1) Outline of the Disc Reproduction Device

(2.2) Construction Elements of the Disc Reproduction Device

(2.2.1) Disc Reproduction Device . . . Construction of Signal SeparatingUnit 86

(2.2.2) Disc Reproduction Device . . . Construction of SystemControlling Unit 93

(2.2.2.1) Specification of Entry Program Chain by System ControllingUnit 93

(2.2.2.2) Operation Example 1 . . . Reproduction Control for Video TitleSet v1

(1) Physical Construction of the Optical Disc

FIG. 1A shows the appearance of the optical disc while FIG. 1B shows itscross-section and FIG. 1C shows an enlargement of the circled part ofFIG. 1B. Starting from the bottom of this figure, DVD 107 is formed of afirst transparent substrate 108, an information layer 109, a bondinglayer 110, a second transparent substrate 111 and a print layer 112 forprinting a label.

The first transparent substrate 108 and the second transparent substrate111 are reinforcing substrates which are made of a same material, withboth being around 0.6 mm thick. This is to say, both substrates areroughly 0.5 mm-0.7 mm thick.

The bonding layer 110 is provided between the information layer 109 andthe second transparent substrate 111 to bond them together.

The information layer 109 includes a reflective membrane, such as metalfoil, which is attached to the first transparent substrate 108. Here, ahigh density of indented and protruding pits is formed in thisreflective membrane by a manufacturing process.

The shape of these pits is shown in FIG. 1D. As shown in FIG. 1D, thelength of the pits varies between 0.4 μm and 2.13 μm with the pits beingaligned in a spiral with radial intervals of 0.74 μm between them so asto form one spiral track.

By shining the laser beam 113 on these pits and measuring the changes inthe reflection ratio of the light spot 114 shown in FIG. 1C, informationcan be retrieved from the disc.

The light spot 114 on a DVD has a diameter of around 1/1.6 times thediameter of a light spot on a conventional CD due to an increase in thenumerical aperture NA of the objective lens and a reduction in thewavelength λ of the laser beam.

DVDs of the physical construction described above can store around 4.7GB of information on one side, which is almost eight times the storagecapacity of a conventional CD. As a result, it is possible to achieve agreat improvement in picture quality for moving pictures and to increasethe reproduction time from the 74 minutes which is possible with a videoCD to over two hours.

The substrate technique which has enabled this improvement in storagecapacity is a reduction of the spot diameter D of the laser beam. Here,spot diameter D is given by the equation “D=laser wavelength λ/numericalaperture of objective lens NA”, so that the spot diameter D can bereduced by reducing the laser wavelength λ and by increasing thenumerical aperture of objective lens NA. It should be noted here that ifthe numerical aperture of objective lens NA is increased, comaticaberration occurs due to the relative inclination, known as “tilt”,between the optical axis of the beam and the disc surface. In order tosuppress this phenomenon, DVDs use a transparent substrate of reducedthickness. Such a reduction in the thickness of the transparentsubstrate creates the problem of reduced physical durability for thedisc, although this problem can be overcome by reinforcing DVDs withanother substrate.

Data is read from DVDs using an optical system with a short wavelength(650 nm) red semiconductor laser and an objective lens whose NA(numerical aperture) can be enlarged up to around 0.6 mm. If thethickness of the transparent substrate is reduced to around 0.6 mm, astorage capacity of up to 4.7 GB can be achieved for one side of a 120mm diameter optical disc. With this large storage capacity, there ismore than enough capacity for a whole feature film to be recorded on onedisc, with it further being possible for the manufacturer to includesoundtracks in several different languages. In fact, the storagecapacity of 4.7 GB achieved by this substrate technique allows thestorage of several sets of video and audio data on a same disc.

FIG. 2A shows the arrangement when the spiral track is formed leadingfrom the inner periphery to the outer periphery of the information layer109. Data retrieval from the spiral track is performed in units calledsectors. The internal construction of the sectors is as shown in FIG.2B, with each sector being made up of a sector header area, a user dataarea and an error correction code storage area.

The sector addresses in the sector header area are used to identify eachsector. These sector addresses are used by the disc reproduction deviceto find sectors which are to be read.

The user data area stores 2 KB of data.

The error correction code storage area stores an error correction codefor the user data area in the same sector. When reading the user dataarea in the same sector, the disc reproduction device uses the errorcorrection code to detect any errors which it then corrects. Thisensures that data retrieval is reliable.

(1.1) Logical Construction of the Optical Disc

FIG. 3A shows the logical construction of the optical disc. As shown inFIG. 3A, the physical sectors are arranged in ascending order of sectoraddresses, with the disc being broadly classified, by means ofidentification information included in the sector addresses, into alead-in area, a volume area and finally a lead-out area.

The lead-in area stores operation stabilization data and the like whichis used when the DVD player starts reading data from the optical disc.The lead-out area informs the reproduction device of the end ofreproduction and does not store meaningful data.

The volume area FIG. 3B stores the digital data which makes up anapplication, as well as managing the physical sectors to which thevolume area belongs as logical blocks. These logical blocks areidentified by serial numbers which are assigned to consecutive physicalsectors, with the first physical sector in the data recording area beingassigned the number zero. The enlarged portion “b301” of FIG. 3C shows agroup of logical blocks in the volume area. Here, the figures, #m, #m+1,#m+2 and #m+3 which are appended to the logical blocks in this circledarea are the logical block numbers.

As shown in FIG. 3B, the volume area includes a volume management areaand a file area.

The volume management area stores file system management informationwhich is used to manage a plurality of logical blocks as files, inaccordance with ISO13346 Standard. The file system managementinformation shows the relations between the file names for a pluralityof files and addresses of the groups of logical blocks which contain thecorresponding files. This file system management information is used bythe disc reproduction device to access the disc in file units. Morespecifically, on being given a file name, the disc reproduction devicerefers to all the system management information to calculate all thegroups of logical blocks for the file, before accessing these groups oflogical blocks to fetch the desired digital data.

FIG. 3D and FIG. 3E show the file area. As shown in the drawing, thefile area stores a Video Manager and a plurality of Video Title Sets,each of which includes a plurality of consecutive files whose recordingpositions are calculated from the file system management information.Here, the reason these files are consecutive is that the data size ofthe moving picture data is so large that if the data were included in afile, the file size would exceed 1 GB.

The Video Title Set stores a group of one or more DVD applicationscalled titles. An example of such a group is a movie application inwhich a plurality of titles, namely a general release version and ano-cut version of the same movie, are grouped together. Here, since muchof the image data is common to both versions, greater efficiency can beachieved when the versions are managed together as a group.

In FIG. 3F, the Video Title Set V1 is an interactive software titlecalled “Travel Mook”. This interactive software title is achieved by thedata structure characteristic to the optical disc of the presentembodiment.

The interactive software “Travel Mook” is a movie book, which means thatit is an electronic publication which includes a number of pieces ofhigh-quality video footage which are twenty or thirty minutes long andwhich has a logical construction modelled on a book in that itsreproduction routes have a list of contents and chapters.

This “Travel Mook” is a title set which is made up of three titles whichare “Hawaiian Island Course”, “Saipan Course” and “Guam Course”.

The Video Manager stores information relating to menus which allow theuser to select a title to be reproduced out of all of the titles storedin the plurality of Video Title Sets.

The following is a detailed explanation of the Video Title Set and theVideo Manager.

(1.1.1) Logical Construction . . . Video Title Set

FIG. 4 shows the data construction of the Video Title Set. The VideoTitle Set includes a plurality of pieces of multimedia data called videoobjects (VOBs) in addition to Video Title Set management information formanaging the reproduction order of the video objects (VOBs).

(1.1.1.1) Video Title Set . . . Video Object (VOB)

A video object (VOB) is multimedia data which includes digital video,digital audio, a sub-picture image and management information. It shouldbe noted for the present example of “Travel Mook”, VOB#1, VOB#2, VOB#3,. . . shown in FIG. 4 respectively include a scene showing the blue skyand clear ocean of the Hawaiian Islands, a scene showing the bustlingcity streets and a scene showing young people enjoying surfing at thebeach.

A video object (VOB) includes a plurality of VOB units (hereinafter,VOBU) aligned in a time series. Each VOBU is a piece of reproductiondata with a reproduction period ranging from about 0.5 to 1.0 secondswhich, as indicated by the arrows in FIG. 4, is more specifically madeup of a variety of data packs which include sets of managementinformation packs, video packs, audio packs A-C and sub-picture packsA-B. Each of these data packs are 2 KB long, with digital data sequencescalled elementary streams of each of video data, audio data, sub-picturedata, and control data being generated by recomposing these packsaccording to their type. Here, each VOB is made up of a program streamor system stream which includes a plurality of these elementary streams.

It should be noted that for ease of understanding, the pack data in eachVOBU in FIG. 4 and FIG. 5A has been arranged in a same order, although,with the exception of the management information packs being stored atthe front, it is unnecessary for the same types of pack data to bestored next to each other since they are retrieved by the reproductiondevice after having first been stored in a buffer, so that the differenttypes of pack data may be stored in a mixed up order in a VOBU. Also,the total number of packs in a VOBU and the number of packs of each typemay not be the same in different VOBUs since the video data, audio data,and sub-picture data are made up of variable-length compressed data. Infact, each VOB unit may have a completely different number of packs.Also, though the VOB unit of the present embodiment is shown as havingonly two video packs, in reality the data transfer rate to areproduction device which is assigned solely to video data is in theregion of 4.5 Mbits, so that normal video data which does not representa still image will be made up of several hundred of such video packs.

The video packs stored in a VOB form at least one piece of digital videodata called a GOP (Group of Picture). Here, a GOP is a standard amountof compressed digital moving picture data which is used duringdecompression and which equates to about 12 to 15 frames of image data.This GOP is stipulated under MPEG2 (Moving Pictures Experts Group,ISO11172, ISO13818).

FIG. 5A shows the relation between each pack in a VOB and one scene ofvideo data. From the top, this drawing shows the video material for thescene, the VOB, three types of audio material and two types of subtitlematerial. The downward arrows indicate how the video material isrecorded in the data fields of each pack.

By following the downward arrows it can be seen that the video from thestart of the scene to the point 0.5 seconds into the reproduction isstored in the data fields of video packs 1 and 2 in VOBU 1 having beencoded into I-pictures (Intra-Pictures), P-pictures (Predictive-Pictures)and B-pictures (Bidirectionally predictive Pictures). It should be notedhere that as described above, there are in fact hundreds of such packsstored in a VODU but, for case of understanding, the present explanationuses the premise of there being only two packs. Similarly, the videofrom the 0.5 second point to the point 1.0 second from the start isstored in the data fields of video packs 3 and 4 in VOBU 2 having beencoded into I-pictures, P-pictures, and B-pictures. Though not shown inthe drawing, the video from the 1.0 second point to the point 1.5seconds from the start is recorded in the data fields of the video packsin the next VOB unit.

For the “Travel Mook”, actual footage of a beach full of foreigntourists and actual footage of a coral reef and shoals of colorfultropical fish are coded into many thousands of I-pictures, P-pictures,and B-pictures which are then distributed and stored among the datafields of the two packs in each GOP. Using such distributed recording,the above beach scene and reef scene are stored in the “Travel Mook”.Here, the data which is distributed among the data fields in each VOB iscalled video data.

The following are separate explanations of the packs which form each VOBunit, with reference to FIGS. 6A—6D.

(1.1.1.1.1) Video Object (VOB) . . . Video Pack

FIG. 6A shows the data construction of a video pack. Each video packincludes a pack header, a packet header, and a data field as stipulatedunder MPEG and is 2 KB in size. The pack header includes a pack startcode and an SCR (System Clock Reference) as stipulated under MPEG. Thepacket header includes a stream ID, a packet length, an STD (SystemTarget Decoder) buffer scale size, a PTS (Presentation Time Stamp), anda DTS (Decoding Time Stamp) as stipulated under MPEG.

As shown in this drawing, the stream ID is set as “1110 0000.” Thisindicates that the elementary stream formed by this pack is a videostream.

The SCR and PTS in the video pack are used to adjust the synchronismwith the decoding of audio packs and sub-picture packs. Morespecifically, the video decoder in the disc reproduction device sets thestandard clock based on the SCR, decodes the moving picture data in thedata field and waits for the standard clock to show the time given bythe PTS. When such time is shown, the decoding results are output to thedisplay side. By waiting until the time given by the PTS, synchronismerrors between the moving picture data and sub-picture data/audio dataduring output can be resolved.

(1.1.1.1.2) Video Object (VOB) . . . Audio Pack

FIG. 6B shows the data construction of audio packs A-C. This dataconstruction is almost the same as that of the video pack shown in FIG.6A except that the stream ID of the packet header is set as “1011 1101”and that a substream ID of eight bits is set at the beginning of thedata field, these being shaded in FIG. 6B. The stream ID is set as “10111101” to indicate that the element stream formed by the pack is privatestream 1. MPEG stipulates that the private stream is a stream which isused for any kind of data aside from video streams or MPEG audiostreams. In the present embodiment, private streams are used for audiodata other than the MPEG audio stream.

In the same way as the video pack, the pack header of the audio packincludes a pack start code and an SCR as stipulated under MPEG. Thepacket header includes a stream ID, a packet length, an STD buffer scalesize, a PTS and a DTS as stipulated under MPEG.

The SCR and PTS of the audio pack are used to adjust the synchronismwith the decoding of video packs and sub-picture packs. Morespecifically, the audio decoder in the disc reproduction device sets thestandard clock based on the SCR, decodes the audio data in the datafield, and waits for the standard clock to show the time given by thePTS. Since audio data is decoded faster than video data and sub-picturedata, the waiting time is much longer for audio data. When the specifiedtime is shown, the decoding results are output to the speaker side. Bysetting this waiting based on the content of the PTS, synchronism errorsbetween the audio data and sub-picture data/video data during output canbe resolved.

Each of audio packs A-C have a different setting in the substream ID ofthe data field. In this drawing, while the five bits on the left-handside of the substream ID of audio packs A and B are set as “1010 0,” thecounterpart five bits of audio pack C are set as “1000 0.” This isbecause audio packs A and B are set according to linear PCM method andaudio pack C is set according to Dolby AC-3 method. The linear PCMmethod includes only L and R components, while the Dolby AC-3 methodincludes a surround component in addition to the L and R components.

The other three bits indicate channel numbers. In the present example,three audio elementary streams are identified, two of these being usedfor the linear PCM, method and one being used for the Dolby AC-3 method.A video object can have 8 audio substreams at maximum. In this case, thesubstream ID of each audio substream is appended any of theidentification codes “0” to “7”.

The “data field” stores digital audio according to the linear PCM methodor the Dolby AC-3 method.

The relation between the soundtracks in the three channels and the datafields of the audio packs are described below with reference to FIG. 5A.FIGS. 5B, 5C, and 5D are disclosures in more detail of the respectivepacks shown in FIG. 5A. As shown by the arrows extending from the audiomaterial to the audio packs in the VOBs in FIG. 5, the soundtracks onthe three channels are encoded according to the two methods and arerecorded in the data fields of the audio packs in units of about 0.5seconds. This is to say, the soundtrack on the A channel for the periodfrom the start of the scene to a point 0.5 seconds into the scene isrecorded in the data field of audio pack A-1 in VOB unit 1, while thesoundtrack for the period from the 0.5 second point to the 1.0 secondpoint is recorded in the data field of audio pack A-2 in VOB unit 2.Although not shown in the drawing, the soundtrack for the period fromthe 1.0 second point to the 1.5 second point is recorded in the datafield of audio pack A-3 in VOB unit 3. It should be noted here that inthe same way as described above, the audio is synchronized with thevideo using the PTS, so that it is unnecessary for audio data whichmatches the video data in a VOBU to be included in the same VOBU, sothat it may often end up being stored in a preceding VOBU.

In the same way as described above, the soundtrack on the B channel forthe period from the start of the scene to a point 0.5 seconds into thescene is recorded in the data field of audio pack B-1 in VOB unit 1,while the soundtrack for the period from the 0.5 second point to the 1.0second point is recorded in the data field of audio pack B-2 in VOB unit2. Although not shown in the drawing, the soundtrack for the period fromthe 1.0 second point to the 1.5 second point is recorded in the datafield of audio pack B-3 in VOB unit 3.

Also, the soundtrack on the C channel for the period from the start ofthe scene to a point 0.5 seconds into the scene is recorded in the datafield of audio pack C-1 in VOB unit 1, while the soundtrack for theperiod from the 0.5 second point to the 1.0 second point is recorded inthe data field. of audio pack C-2 in VOB unit 2. Although not shown inthe drawing, the soundtrack for the period from the 1.0 second point tothe 1.5 second point is recorded in the data field of audio pack C-3 inVOB unit 3.

The sets of data on the three channels which are stored in the datafields of the respective audio packs A-C are hereinafter called audiodata A, audio data B and audio data C. As one example, audio data A canbe set as an English soundtrack, audio data B can be set as a Frenchsoundtrack and audio data C can be set as a Japanese soundtrack, withthe user being able to switch between them.

(1.1.1.1.3) Video Object (VOB) . . . Sub-Picture Pack

FIG. 6C shows the construction of the sub-picture pack. As can be seenby comparing FIGS. 6B and 6C, the construction is basically the same asthat of the audio pack shown in FIG. 6B. This is to say, eachsub-picture pack is made up of a “pack header”, a “packet header” and a“data field”, with the start of the data field being provided with asubstream ID which is eight bits in length.

The pack header of the sub-picture pack, like that of the audio pack,includes a pack start code and an SCR as stipulated under MPEG. Thepacket header includes a stream ID, a packet length, an STD buffer scalesize, a PTS, and a DTS as stipulated under MPEG.

The SCR and PTS of the sub-picture pack are used to adjust thesynchronism with the decoding of video packs and audio packs. Morespecifically, the sub-picture decoder in the disc reproduction devicesets the standard clock based on the SCR, decodes the sub-picture datain the data field and waits for the standard clock to show the timegiven by the PTS. This waiting is necessary because the load fordecoding moving picture data differs from that for audio data. Thedecoding of moving picture data includes the prediction of the motioncompensation as well as run-length decoding, intra decoding, andin-field decoding. Also, while decoding the moving picture data isindispensable for each VOB unit, subtitles may be decoded at intervalsof several seconds. When the time given by the SCR is reached, thedecoding results are output to the display side. With this waiting basedon the description of the PTS, synchronism errors between thesub-picture data and audio data/moving picture data during output can beresolved.

In the same way as the audio pack, the stream ID in the packet header ofthe sub-picture pack is set as “1011 1101”, which indicates the privatestream. However, the first three bits of the substream ID in sub-picturepacks A and B are set as “001”. See the shaded part in the drawing.

The other five bits indicate channel numbers. In the present example,two sub-picture elementary streams are identified. It should be notedthat the elementary streams for audio and sub-pictures aside from thevideo elementary streams are called substreams. A video object can have32 sub-picture substreams at maximum. In this case, the substream ID ofeach sub-picture substream is appended by any of the identificationcodes “0” to “31”.

The data field stores image data compressed with run-length coding anddisplay control information used for displaying the image data. Thisimage data is displayed on the screen as the sub-pictures. The displaycontrol information is used to control scroll up/down, color paletteconversion and contrast conversion for the displayed sub-pictures. Thesesub-pictures are superimposed on the moving pictures in the same VOBunit or after.

In FIG. 5, a VOB unit includes two sub-picture packs A and B.Accordingly, the subtitles on the two channels are distributed andrecorded in the data fields of these sub-picture packs. For thisexample, English subtitles are included in sub-picture data A, andFrench subtitles are included in sub-picture data B, with the user beingable to switch between the languages.

Also, the sub-picture data may be used as a menu. FIG. 7 shows anexample menu used in the application “Travel Mook”. Here, there are twoselectable menu objects, “Recommended Course” and “Choose your ownItinerary”, with these being called items. The use of the sub-picturesas items in a menu will be described later.

(1.1.1.1.4) Video Object (VOB) . . . Management Information Pack

At least one pack of management information is included in each VOB unitat its start, with the included management information being effectivewhile the VOB unit in question is reproduced. FIG. 6D shows theconstruction of a pack of management information. While each of thevideo pack, audio pack, and sub-picture pack is made up of one packet, aset of management information is formed of two packets. These twopackets are respectively a PCI (Presentation Control Information) packetand a DSI (Data Search Information) packet. The management informationpack includes a pack header, a system header, a packet header for a PCIpacket, a data field for a PCI packet, a packet header for a DSI packet,and a data field for a DSI packet. The system header stores themanagement information pack for the entire VOB unit conforming to MPEG,which is, the transfer rate for the whole VOB unit, the transfer ratefor each of the moving picture stream, audio stream, sub-picture stream,and indication of buffer size.

The stream IDs of both packet headers are set as “1011 1111.” whichindicates private stream 2. These are shown as having been shaded inFIG. 6D.

(1.1.1.1.4.1) Management Information Pack . . . DSI Packet

FIG. 8 shows the construction of the DSI packet. As shown in thedrawing, a DSI packet includes the DSI standard information, and trickplay information. The trick play information referred to here includeshigh speed search information, angle information and the like.

The DSI standard information indicated the logical block number of themanagement information pack and includes addresses of I-pictures of thevideo pack of the management information in question and the same GOPunit. For the example shown in FIG. 8, the DSI standard informationincludes addresses for the three I-pictures included in the GOP unit inquestion.

The high-speed search information is a table which stores a skip addressfor skip reproduction for each different skip amount. This skipreproduction can be performed in the standard reproduction direction orin the reverse reproduction direction with the standard reproductiondirection being the direction where following the spiral track resultsin movement from the inner periphery of the disc to the outer peripheryand the reverse reproduction direction being the direction wherefollowing the spiral track results in movement from the outer peripheryof the disc to the inner periphery. This table uses the address of thepresent management information pack as a standard and stores theaddresses of management information of the closest VOB units at 0.5second intervals in the standard reproduction direction and in thereverse reproduction direction. As one example, for “FWDI 60”, theaddress of a pack of management information of a VOB unit to bereproduced in 30 (60*0.5) seconds time is stored. In the same way, forFWDI 1, 2, . . . 13, 14, 15, 20, 60, 120, 240 and BWDI 1, 2, . . . 13,14, 15, 20, 60, 120, 240, addresses of packs of management informationin a corresponding VOB unit to be reproduced are stored. It should benoted here that the actual speed of this skip reproduction is determinedby a value given by the indication keys for skip reproduction on thedisc reproduction device which indicates which of the above values inthe table is to be used. Also, when the remote controller of the discreproduction device is equipped with a jog disc which enables the skipreproduction speed to be determined according to a variable setting ofrotation angle, variable speed skip reproduction can be performed usingall of the values in the table.

The angle information is a table which lists the storage positions ofthe angle cells in a multiangle section. Here, a multiangle section is asection where a plurality of images where the movement of subject or theprogression of the scene are shown from a plurality of different cameraangles, such as a head-on angle, a side angle, a view from overhead oran angle above and to the side. Here, an angle cell is one part of a VOBwhich includes an image shot at a head-on angle, a side angle, a viewfrom overhead or an angle above and to the side. These angle cells arenumbered 1, 2, 3 etc. The user can specify these numbers using thenumeric keys on the remote controller, so that the disc reproductiondevice reads the management information pack address of the angle cellcorresponding to the indicated number from the appropriate angleinformation and has the optical pickup moved to the appropriate address.If the user presses the key (angle switching key) which indicates thecount up of the angle cell number, the angle cell which is the retrievaladdress for the disc reproduction device can be cyclically changed. Bydoing so, the scene can be reproduced with appropriate switching betweenthe aforementioned angles.

(1.1,1.1.4.2) Management Information Pack . . . PCI Packet

The PCI packet includes Highlight Information which is mainly forinviting the user to make interactive inputs (see FIG. 9B) and PCI useroperation limitation information for stipulating whether specialreproduction execution requests made by the user can be executed. ThisPCI user operation limitation information is an element in the PCIStandard Information shown in FIG. 9A. Here, PCI Standard Information isinformation for indicating the reproduction start time and end time ofthe appropriate VOB units, but since this does not form part of the gistof the present invention, it will not be explained.

The management information pack is located at the start of each VOBunit. After the video pack, audio pack and sub-picture pack in a VOBunit have been read, in the 0.5 second period before the managementinformation pack in the next VOB unit is read, the Highlight informationand the PCI user operation limitation information are expanded by thedisc reproduction device in the buffer with the data constructions asshown in FIGS. 9A-9C. Once this 0.5 second period has elapsed, theHighlight Information and the PCI user operation limitation informationin the buffer are replaced with the Highlight Information and the PCIuser operation limitation information from the next VOB unit. Since thePCI user operation limitation information from a VOB unit is onlyexpanded in the buffer while the video pack, audio pack and sub-picturepack in the same VOB unit are being read, if a key interrupt which is arequest for special reproduction execution occurs during this 0.5 secondperiod, the disc reproduction device can decide, using the PCI useroperation limitation information in question, whether or not to activateinterrupt processing.

As one example, if, in the same VOB unit as a set of PCI user operationlimitation information, the video pack, audio pack and sub-picture packcontain material which is a commercial or licensing message, the PCIuser operation limitation information is set so as to forbid theactivation of interrupt processing for fast forward. In this case, theactivation of interrupt processing for fast forward reproduction throughthe commercial or licensing message content is prevented by the PCI useroperation limitation information. In this way, the PCI user operationlimitation, information is used to stipulate whether the activation ofinterrupt processing is permitted or not in accordance with the contentof the images included in the video pack which belongs to the same VOBunit.

(1.1.1.1.4.2.1) PCI Packet—PCI Standard Information

The data composition of the PCI user operation limitation information isshown by the expansion expressed using the dotted line in FIG. 9A. Here,other forms of special reproduction aside from fast forward are present,with the activation of each of these special functions beingrespectively permitted or prohibited by the PCI user operationlimitation information. The columns in FIG. 9A show whether theactivation of interrupt processing for the various kinds of specialfunctions, such as PCI Standard Information-Backward Scan ( ), PCIStandard Information—Previous PG search ( ) and the like arerespectively permitted or prohibited.

PCI Standard Information-Backward Scan ( ) uses one bit of informationto express, when executing a rewind operation a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Forward Scan ( ) uses one bit of information toexpress, when executing a fast-forward operation a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Pause On ( ) uses one bit of information toexpress, when executing a pause of reproduction a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Angle Change( ) uses one bit of information toexpress, when executing a change of angle cell a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Sub-Picture Stream Change( ) uses one bit ofinformation to express, when executing a change of sub-picture a certaintime period after the management information including this PCI StandardInformation has been read, whether or not the execution of interruptprocessing is permitted.

PCI Standard Information-Audio Stream Change( ) uses one bit ofinformation to express, when executing a change of audio a certain timeperiod after the management information including this PCI StandardInformation has been read, whether or not the execution of interruptprocessing is permitted.

The explanation of the PCI Standard Information-Menu Call (Volume),PrevPVPG-Search( ) and TopPG-Search will be made later. This is becausethese fields show whether or not functions which have not yet beenexplained are permitted.

(1.1.1.1.4.2.2) PCI Packet—Highlight Information

The Highlight Information is control information for receivingoperations made in respect to menus displayed using the sub-picturepacks, with its data composition being shown in FIG. 9B. As shown byreference numeral “h2” in FIG. 9B, the Highlight Information is furthercomposed of highlight standard information, item color information anditem information #1, #2, #3, #4, #5 . . . #36. The sets of iteminformation #1, #2, #3, #4, #5 . . . #36 are displayed when themanagement information in question is read and contain the respectiveitems. For the example shown in FIG. 7, the two menu objects“Recommended Course” and “Choose your own Itinerary” are the two items,so that in this case item information from item information #1 to iteminformation #2 is entered in the Highlight Information. It should benoted here that this region is of fixed length, but that validinformation is not stored in the item information for items which arenot actually used. As mentioned above, a maximum of 36 sets of iteminformation can be set, which is to say, a maximum of 36 menu objectscan be displayed on one screen.

The following is a detailed explanation of the composition of theHighlight Information with, before that, a brief description of themenus used by the reproduction device.

Firstly, the items which are menu objects can have two states, thesebeing a standard state and a selected state, with these being switchedby the user making a selection of a menu object or a confirmationoperation. For the example shown in FIG. 7, when the menu is displayed,a default operation is activated and the disc reproduction devicedisplays item #1 in a selected state and the remaining items in thestandard state. Here, if the standard state for all items is a displayusing the color white, selected state is a display using the color blueand confirmed state is a display using the color red, then only the menuobject corresponding to item #1 is displayed using the color blue. Bydoing so, the user can readily understand which menu object is currentlybeing selected (the menu object in question may also be indicated usinga cursor) and that the reproduction device is waiting for confirmation.If the user wishes to change the selected menu object, he/she may makean operation using the cursor keys on the remote controller of thereproduction device and so indicate their desired selection. Asdescribed later in this specification, when a cursor key on the remotecontroller has been depressed, the disc reproduction device manages theitems to be changed using item numbers. By doing so, item #1 is returnedto the color for the standard state, which is to say white, while thenewly selected item is displayed using blue, the color for the selectedstate. When the user s selected menu item is displayed in the selectedstate, the user can confirm the item in the selected state by depressingthe confirm key on the remote controller. An item which is confirmed inthis way has its color changed from blue to red, with a predeterminedcommand being executed for the confirmed state. For the example shown inFIG. 7, reproduction control is performed according to the confirmedmenu object.

This concludes the description of the menus and the explanation willproceed to the details of the Highlight Information.

(1.1.1.1.4.2.2.1) Highlight Information—Item Color Information

The “Item Color Information” is information for the selection color andconfirmation color to be used for items as shown by reference numeral b6in FIG. 9B. The selection color is the color given to an item which hasbeen selected by the user or by a default, while the confirmation coloris the color given to an item whose selection has been confirmed by theuser. There are three separate combinations of these selection color andconfirmation color, with each indication of these colors being made upof an indicated color and a mixing ratio with a background color.

(1.1.1.1.4.2.2.2) Highlight Information—Item Information

As shown by the reference numeral b3 in FIG. 9B, each set of “ItemInformation #1, #2, #3, #4, . . . #36” is made up of a color patternnumber, start coordinate X1, start coordinate Y1, end coordinate X2, endcoordinate Y2, peripheral position information and a highlight commandfield.

The color pattern number specifies a color pattern for a combination ofa selection color and a confirmation color included in the item colorinformation. Start coordinate X1, start coordinate Y1, end coordinateX2, and end coordinate Y2 indicate the range of an area to which theindicated color and mixing ratio are applied when an item is selected orconfirmed by the user.

The peripheral position information is made up of an “item numberindicated when up key is depressed”, an “item number indicated when downkey is depressed”, an “item number indicated when left key is depressed”and an “item number indicated when right key is depressed”, with theseindicating to the reproduction device the item chosen by the indicatingdevice, such as the cursor keys on the remote controller.

The highlight command field is a command field which is related to eachset of item information, as shown by the reference numeral y303 in FIG.9B. The command written in the highlight command field is executed bythe disc reproduction device after the related item is confirmed by theuser. Here, this confirmation operation for the disc reproduction devicecan be made by the user depressing the enter key having indicated theirselected item or by the user pressing the numeric keys and the like. Thecommands that can be written in the highlight command field are branchcommands for branching to a different reproduction route andaddition/subtraction commands for adding or subtracting points accordingto the confirmation operation of an item.

An example of a branch command in the highlight command field in theitem information is shown below.

{Case 3}

1. “Recommended Course”—branch command “Link PGC#2”

2. “Choose your own Itinerary”—branch command “Link PGC#3”

In these branch commands written in the highlight command field of theHighlight Information, the numerical values for PGCs 2 and 3 show thePGC numbers allocated to sets of PGC information in the Video Title Setmanagement information. Here, a set of PGC information is mainlyinformation for setting a reproduction route, with there being aplurality of such sets of information in the Video Title Set managementinformation. As one example, if, during the reproduction of VOB#9 andthe reproduction of the menu shown in FIG. 7, the user makes aconfirmation operation for item 1, then the branch command “Link PGC#2”written in the highlight command field of the Highlight Information isretrieved and executed. By doing so, the reproduction route of theoptical disc branches to PGC information #2.

(1.1.1.1.4.2.2.3) Highlight Information—Highlight Standard Information

As shown by the row indicated by the reference numeral h4 in FIG. 9C,the highlight standard information is made up of “Flag showing changefrom previous VOB”, “Valid range starting position for HighlightInformation” and “Valid range ending position for HighlightInformation”.

“Flag showing change from previous VOB” has a field which is two bitslong. If this field is set as “00”, this means the Highlight Informationwhich includes this “Flag showing change from previous VOB” does notcontain valid item color information or valid information. When thisfield is set as “01”, it means that the Highlight Information whichincludes this “Flag showing change from previous VOB” is valid for thepresent pack onwards. The newly valid Highlight Information is thenwritten into the Highlight Information buffer (this is a buffer in thedisc reproduction device for storing the Highlight Information and isexplained later in the text) in the disc reproduction device. When thisfield is set as “10”, it means that the Highlight Information in theprevious VOB unit is still valid for the present VOB unit. In this case,the Highlight Information buffer does not have its content overwritten.Finally, when this field is set as “11”, it means that the only thehighlight command in the Highlight Information from the previous VOBunit is changed. In this case, it indicates to the disc reproductiondevice to overwrite only the highlight command in the highlight buffer.

Putting this in other words, by using this “Flag showing change fromprevious VOB”, the disc reproduction device can check whether thesetting information for menu objects has changed, so that in addition tobeing able to renew the Highlight Information for each VOB unit, thedisc reproduction device can also detect when it is unnecessary tochange the stored information and thereby avoid having to execute atroublesome renewal process for each VOB unit.

Here, the “Valid range starting position for Highlight Information” and“Valid range ending position for Highlight Information” show the validrange for the Highlight Information.

The data compositions of each VOB and each pack as shown in FIG. 4 areas described above. The following is a comparative explanation withreference to FIGS. 10A-10C of the differences between the data contentsof the various VOBs in the Video Title Set shown in FIG. 4.

In VOB#1 in FIG. 10A, the several-minute period which includesGOP00-GOP200, as shown by the arrows drawn in FIG. 10A, is actualfootage which includes commercials for tour operators and airlines.

Also, the several-minute period which includes GOP250-GOP450, as shownby the arrows drawn in FIG. 10A, is actual footage which depicts afamous beach.

In VOB#2 in FIG. 10A, the several-minute period which includesGOP00-GOP200, as shown by the arrows drawn in FIG. 10A, is actualfootage which gives an introduction of the facilities at a high classhotel in the area. Also, the several-minute period which includesGOP250-GOP450, as shown by the arrows drawn in FIG. 10A, is actualfootage which explains room rates, as well as check-in and check-outprocedures.

In VOB#3 in FIG. 10A, the several-minute period which includesGOP100-GOP200, as shown by the arrows drawn in FIG. 10A, is actualfootage which gives an introduction of a budget hotel.

As shown in FIG. 10B, VOB#4 contains a several-minute period whichincludes GOP100-GOP200, including a video pack, sub-picture pack and amanagement information pack for displaying a first menu. Here, the videopack stores a background image for the menu, the sub-picture pack storesgraphics for having the menu items changed to the selection color andthe confirmation color and the management information pack storescommand information to be executed when the menu objects are confirmed.Here, the information for user interaction assigned to each menu objectis called an item. The present menu contains two items for displayingtwo courses which are a deluxe course and a budget0 course based on thestandard of hotel used, with these being related to item information #1and item information #2 in the management information pack. Iteminformation #1 includes a command “Link PGC#5” for switchingreproduction route and item information #2 includes a command “LinkPGCt6” for switching reproduction route.

In VOB#5, the several-minute period which includes GOP100-GOP200includes a sub-picture pack for displaying a second menu. This menuincludes items for selecting one of a “Diving course” and “CitySightseeing Course”, with these items being respectively related to PGCitem information #1 and PGC item information #2. Item information #1includes a command for switching reproduction route to PGC7 and iteminformation #2 includes a command for switching reproduction route toPGC8.

In VOB#6, the several-minute period which includes GOP100-GOP200, asshown by the arrows drawn in FIG. 10, is actual footage of tropicalfish.

In VOB#7, the several-minute period which includes GOP100-GOP200, asshown by the arrows drawn in FIG. 10B, is actual footage which gives anintroduction of diving spots. The several-minute period which includesGOP300-GOP4OO, meanwhile, is actual footage which gives an introductionof diving precautions and emergency methods.

In VOB#8, the several-minute period which includes GOP100-GOP200 isactual footage which gives an introduction of places of interest in thecity. As shown by the arrows in the drawing, the several-minute periodwhich includes GOP300-GOP400 is actual footage which describes generalprecautions to be taken around town as well as contacts in case ofemergency.

In VOB#9, the several-minute period which includes GOP100-GOP200includes a sub-picture pack for displaying a third menu. This menuincludes items for selecting one of a “Recommended Course” and “Chooseyour own Itinerary”, with these items being respectively related to PGCitem information #1 and PGC item information #2 in the PCI of themanagement information pack in the corresponding period. Iteminformation #1 includes a command “LinkPGC#2” for switching reproductionroute to PGC#2 and item information #2 includes a command “LinkPGC#3”for switching reproduction route to PGC#3.

The part from GOP00-GOP200 of VOB#1 which corresponds to commercials isset so that in the PCI user operation limitation information, PCIStandard Information-Forward Scano is not permitted. This means that theuser is not able to make a fast forward operation and therefore preventsthe user from missing the inserted commercials.

(1.1.1.2) Video Title Set Management Information

The Video Title Set management information stores information formanaging a plurality of reproduction orders of the video objectsdescribed above. This is to say, if the Video Title Set stores the aboveexample of a “Travel Mook”, the Video Title Set management informationstores a plurality of program chains (PGC) for stipulating how thereproduction proceeds when each of the courses for Hawaiian Islands,Guam and Saipan are selected.

FIG. 11 shows the internal construction of the Video Title Setmanagement information. As shown by reference numeral a5 in FIG. 11, theVideo Title Set management information is made up of a Video Title Setmanagement table, a Video Title Set title search pointer table and PGCmanagement information table.

The Video Title Set management table is the header information of theVideo Title Set management information and stores pointers for thestorage positions of the Video Title Set unit title search pointer tableand the PGC management information table.

The Video Title Set unit title search pointer table is the index of theplurality of program chains stored in the PGC management informationtable and specifies a pointer for the storage position of a programchain to be executed first in each title. In the present embodiment,this table stores the first piece of PGC information for each of thecourses for Hawaiian Islands, Guam and Saipan in the “Travel Mook”.

As shown by reference numeral a6, the PGC management information tablestores a plurality of sets of PGC information #1, #2, t3, #4, . . . #nwhich each relate to all of the video objects stored in a Video TitleSet. Here, any one of these sets of PGC information is stored in abuffer in the disc reproduction device, so that by reading this buffer,the disc reproduction device can retrieve VOBs in the reproduction ordergiven in this PGC information and sends them in order to the decoder.

When the retrieval of one reproduction route is complete, another set ofPGC information is read from the optical disc and is written into thebuffer so as to replace the PGC information which was hitherto used. Byreading this new PGC information from the buffer, the disc reproductiondevice retrieves VOBs in the reproduction order given in this PGCinformation and sends them in order to the decoder. By doing so, sets ofPGC information successively replace each other in the buffer and thedisc reproduction device can obtain the reproduction routes from theoptical disc without interruption, based on which it retrieves the VOBs.

Here, each set of PGC information includes a reproduction order of atleast one video object. There are also cases where two or more sets ofPGC information indicated the reproduction of a same video object. Usingthe example Video Title Set shown in FIG. 4, suppose a set of PGCinformation stores the reproduction order VOB#1-VOB#2-VOB#3-VOBπ4. Inthis case, these VOBs are reproduced in the written order. Similarly, ifdifferent set of PGC information stores a reproduction order ofVOB#3-VOB#2-VOB#1-VOB#4, these VOBs are reproduced in that order.

The following is an explanation of the data construction of the PGCinformation.

(1.1.1.2.1.) Video Title Set Management Information —PGC information

As described above, sets of PGC information are information for settingreproduction routes, with this information mainly indicating what VOBsincluded in the same Video Title Set are to be reproduced and in whichorder. Here, the information “Following reproduction route”, “How VOBsreproduced by this information are grouped”, and “Whether to activateinterrupt processing for special reproduction function duringreproduction of a VOB if requested by user” is added to the reproductionroute in this PGC information. Since these various kinds of controlinformation are added to each reproduction route, each set of PGCinformation is made up of “PGC connection information”, “PGC StandardInformation”, “VOB address information table” and “PGC command table”,as shown by reference numeral a7 in FIG. 12. “VOB address informationtable” indicates to the reproduction device which VOBs in this PGCinformation should be retrieved and in which order. Moreover, it alsoshows from which point to which point on the optical disc each VOB inthe reproduction order is stored, which these ranges being scanned bythe optical. pickup of the disc reproduction device. The VOB retrievalorder and scanning range for the optical pickup when reading each VOBare expressed in a list of VOB address information. The table of VOBaddress information is indicated by the reference numeral a9. Asindicated by this reference numeral a9, in the present embodiment theVOB address information is expressed as a reproduction time of a VOB, aVOB offset and a number of blocks in a VOB. When retrieving a VOB, thedisc reproduction device uses the number of offsets and the likeincluded in the VOB address information to calculate a logical blocknumbers of the logical blocks in which the VOB is stored, beforescanning only the number of blocks indicated in “number of blocks” onthe track starting from the calculated logical block in either thestandard reproduction direction or in the reverse reproductiondirection.

The PGC connection information is information which shows “Whatreproduction route follows the present one” and stores connectioninformation showing what PGC information is to be retrieved and storedin the buffer after the present PGC information. On completingreproduction using one set of PGC information, the disc reproductiondevice determines the next set of PGC information in accordance with the“PGC connection information”, retrieves the determined set of PGCinformation from the optical disc and overwrites the retrieved PGCinformation into the buffer. By doing so, the PGC information in thebuffer is renewed and reproduction control can continue using thereproduction route given by the renewed PGC information.

The “PG Map” is information which shows “How VOBs reproduced by thisinformation are grouped” and, a indicated by the reference numeral a10in FIG. 12, has a data construction in the form of a table wherein aplurality of PG numbers are related to their entry VOBs. Here, a PG(short for ProGram) is a group of a plurality of VOBs in thereproduction order of the corresponding PGC information, while an entryVOB is the VOB at the first position in each PG.

As one example, PGC#10 includes a reproduction order for 9 VOBs in theorder VOB#1, #2, #3, #4, #5 . . . #9, and VOB#1 is set as the entry VOBof PG#1, VOB#3 is set as the entry VOB of PG#2 and VOB#6 is set as theentry VOB of PG#3. In this case, VOB#1-VOB#2 are grouped into PG#1,VOB#3-VOB#5 are grouped into PG#2 and VOB#6-VOB#9 are grouped into PG#3.

The PG map is provided for reading by the disc reproduction device whenan indication to change the retrieval position is given by the user.Here, a “Retrieval position change indication” is an indication such as“advance to Next PG”, “return to Previous PG” or “return to Top PG”which is given by the user.

If the user gives a “return to Previous PG” while the disc reproductiondevice is retrieving VOB#4, then for the example PG map given above, thename of the PG to which VOB#4 belongs and the name of its preceding PGand its entry VOB are retrieved by the disc reproduction device. Here,VOB#4 belongs to PG#2 and the previous PG is PG#1, so that the discreproduction device retrieves and commences the reproduction of theVOB#1 which is the entry VOB of PG#1. If the user gives an “advance toNext PG” indication while the disc reproduction device is retrievingthis VOB#4, the name of the PG to which VOB#4 belongs and the name ofits succeeding PG and its entry VOB are retrieved by the discreproduction device. Here, VOB#4 belongs to PG#2 and the succeeding PGis PG#3, so that the disc reproduction device retrieves and commencesthe reproduction of the VOB#6 which is the entry VOB of PG#3.

If the user gives a “return to Top PG” while the disc reproductiondevice is retrieving VOB#4, then for the example PG map given above, thename of the PG to which VOB#4 belongs and the name of the top PG in thePG map and its entry VOB are retrieved by the disc reproduction device.Here, VOB#4 belongs to PG2 and the top PG is PG1, so that the discreproduction device retrieves and commences the reproduction of theVOB#1 which is the entry VOB of PG1.

The “PGC command table” stores addition/subtraction commands and branchcommands which are added to the “VOB address information table”. Thedisc reproduction device executes the commands written in this tablebefore and after reading a VOB according to the VOB address informationtable.

As shown by reference numeral all in FIG. 12, the “PGC user operationlimitation information is a table which lists, when a key interruptsignal has been generated for special reproduction, whether thefunctions indicated by these key interrupts are to be executed(permitted) or refused (not permitted). It is used in a similar way tothe PCI user operation limitation information included in the managementinformation pack. However, while the PCI user operation limitationinformation is included in a VOB unit, the PGC user operation limitationinformation is included in the PGC information, so that a firstdifference is that the PGC user operation limitation information isexpanded in a buffer for a much longer time than the PCI user operationlimitation information.

More specifically, since there are as many sets of PCI user operationlimitation information as there are VOB units, this information iscontinually updated every 0.5 seconds, while the PGC user operationlimitation information is expanded in the buffer during the period whenall of the VOBs written in the VOB address information table are beingretrieved. Here, once all of the VOBs written in the VOB addressinformation table have been retrieved, the PGC user operation limitationinformation in the buffer is overwritten with the next PGC information.For the example of the “Travel Mook”, the reproduction of all of theVOBs in the VOB address information table can take up to an hour ormore, so that one set of PGC user operation limitation information isexpanded in the buffer for this period of up to an hour or more.

If a key interrupt requesting execution of special reproduction occursduring this period of up to an hour or more, the disc reproductiondevice decides whether or not to execute interrupt processing accordingto the content of the PGC user operation limitation information in thepresent PGC information.

A second difference is that the PCI user operation limitationinformation prevents activation of interrupt processing for specialreproduction only during the period when a specified image content(which can be the commercials or contracts described earlier in thetext) is reproduced out of the period when the VOBs are reproduced, sothat the such interrupts are received the rest of the time. In contrast,the PGC user operation limitation information prevents activation ofinterrupt processing for special reproduction during the reproduction ofthe image content of several VOBs in the VOB position information tablein the same PGC information, regardless of any special image contenttherein.

Also, while the premise for the PCI user operation limitationinformation is that it forbids interrupt processing for specialreproduction only during a period in which a specified image contentappears or otherwise accepts such requests in synchronization with theimage content of each VOB unit, the PGC user operation limitationinformation determines whether to forbid interrupt processing forspecial reproduction or not based on the premise of whatever VOBs aredisplayed successively on the screen by the “VOB address informationtable” in the present PGC information (here, the VOB address informationtable indicates VOBs and so shows how scenes will develop).

In the present example, the “VOB address information table” in PGCinformation #31 is set as only reading the selected VOBs which relate tothe Hawaiian Islands course. Here, the PGC user operation limitationinformation for PGC information #31 forbids the activation of interruptprocessing for fast forward. By doing so, it can be recorded on theoptical disc as a “fast-forward prohibited reproduction route” forviewing a selected scene.

The “VOB address information table” in PGC information #32 is intendedto display a digest image by reading only the first part of all of theVOBs which have actual footage which relates to the Hawaiian Islandscourse. Here, the PGC user operation limitation information for PGCinformation #32 permits the activation of interrupt processing for fastforward. By doing so, it can be recorded on the optical disc as a“fast-forward permitted reproduction route”. Accordingly, the activationof interrupt processing for fast forward when viewing the course in ashort period of time is permitted for PGC information #32. Here, evenwhen the same image content is reproduced by PGC information #31 and PGCinformation #32, a distinction is made so that in the respective casesthe same content is part of a “fast-forward prohibited reproductionroute” and part of a “fast-forward permitted reproduction route”.

A third difference is that while for the PCI user operation limitationinformation, cursor operations and confirmation operations for a menudisplayed by the sub-picture cannot be set as permitted or prohibited,for the PGC user operation limitation information, cursor operations andconfirmation operations for a menu displayed by the sub-picture can beset as permitted or prohibited.

Aside from these three differences, the PGC information may include a“two-sided control structure” by using the PGC user operation limitationinformation. This two-sided aspect refers to invalidation of activationof functions which use fast forward, rewind, angle changing orinteractive operations in the PGC information, even when the controlinformation for such functions is preserved in the managementinformation. With such a two-sided control construction, by setting theuser operation limitation information in the PGC information side, thetitle developer can adjust to what level the control content should beavailable to the user by the DSI packet and the PCI packet in themanagement information. By making such adjustments, reproduction routeswhich can sufficiently achieve interaction with the user andreproduction routes for demonstrations which partially or entirelyexecute interactive control can be provided on a same optical disc, withappropriate switching between these kinds of reproduction routes beingpossible in accordance with the state of the information to bereproduced.

As one example, when there is control using the Highlight Informationsuch as the execution of highlight commands when there is up, down, leftor right cursor movement or a confirmation operation and only theexecution of highlight commands for confirmation operations areprohibited by the PGC user operation limitation information, then up,down, left or right cursor movement according to a user operation ispermitted for reproduction performed using this PGC information, but nomatter how many times the enter key is depressed, no highlight commandwill be executed. For the example in FIG. 8, even if the cursor is movedbetween the items, “Recommended Course” and “Choose your own Itinerary”,the branch commands related to each of these items cannot be executed.

By doing so, PGC information, which is a combination of PGC useroperation limitation information which partially invalidates interactiveoperations and branch commands for automatically determining branchaddresses, can be used in an auto demonstration to be used for salespromotion of the “Travel Mook”. This is to say, by having an automaticdisplay of high quality video footage in a shop, the interest ofcustomers can be aroused and, by allowing the customers to make cursoroperations, the interactive nature of the title can be demonstratedwhile at the same time prohibiting branches achieved through highlightcommands which are the main attraction of such title in the shopdemonstration. Aside from such highly interactive PGC information, byproviding PGC information for a demonstration where interactiveoperations are partially invalidated, switching between the tworeproduction routes of “product” and “demo” can be achieved.

This completes the explanation of the differences with the PCI useroperation limitation information so that the following is an explanationof the details of the PGC user operation limitation information.

The column indicated by the reference numeral all in FIG. 12 shows theseparate indications of whether the activation of interrupt processingfor the various kinds of special reproduction, such as PCI StandardInformation-Backward Scan( ), PCI Standard Information-Previous PGSearch( ), TopPG-Search and the like, are permitted or prohibited.

PCI Standard Information-Backward Scan ( ) uses one bit of informationto express, when executing a rewind operation a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Forward Scan ( ) uses one bit of information toexpress, when executing a fast-forward operation a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Pause On ( ) uses one bit of information toexpress, when executing a pause of reproduction a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Angle Change( ) uses one bit of information toexpress, when executing a change of angle cell a certain time periodafter the management information including this PCI Standard Informationhas been read, whether or not the execution of interrupt processing ispermitted.

PCI Standard Information-Sub-Picture Stream Change( ) uses one bit ofinformation to express, when executing a change of sub-picture a certaintime period after the management information including this PCI StandardInformation has been read, whether or not the execution of interruptprocessing is permitted.

PCI Standard Information-Audio Stream Change( ) uses one bit ofinformation to express, when executing a change of audio a certain timeperiod after the management information including this PCI StandardInformation has been read, whether or not the execution of interruptprocessing is permitted.

Upper Item Select( ), Lower Item Select( ), Right Item Select(, LeftItem Select(, Item Activate( ) stipulate whether operations as describedin the third difference are permitted or prohibited.

Upper Item Select( ) uses one bit of information to express, when theuser depresses the up cursor key during the period when the VOBs arebeing retrieved according to the PGC information included in the PGCStandard Information, whether or not cursor movement to the item abovein accordance with this indication of the moved-to item in theperipheral position information in the Highlight Information ispermitted.

Lower Item Select( ) uses one bit of information to express, when theuser depresses the down cursor key during the period when the VOBs arebeing retrieved according to the PGC information included in the PGCStandard Information, whether or not cursor movement to the item abovein accordance with this indication of the moved-to item in theperipheral position information in the Highlight Information ispermitted.

Left Item Select( ) uses one bit of information to express, when theuser depresses the left cursor key during the period when the VOBs arebeing retrieved according to the PGC information included in the PGCStandard Information, whether or not cursor movement to the item abovein accordance with this indication of the moved-to item in theperipheral position information in the Highlight Information ispermitted.

Right Item Select( ) uses one bit of information to express, when theuser depresses the right cursor key during the period when the VOBs arebeing retrieved according to the PGC information included in the PGCStandard Information, whether or not cursor movement to the item abovein accordance with this indication of the moved-to item in theperipheral position information in the Highlight Information ispermitted.

Item Activate( ) uses one bit of information to express, when the usermakes a confirmation operation during the period when the VOBs are beingretrieved according to the PGC information included in the PGC StandardInformation, whether or not execution of the command in the highlightcommand field related to the indicated item information is permitted.

PGC Standard Information-Menu Call(Volume) uses one bit of informationto express, when the user makes an operation to retrieve the volume menuduring the period when the VOBs are being retrieved according to the PGCinformation included in the PGC Standard Information, whether or notexecution of interrupt processing for this operation. is permitted.

PGC Standard Information-NextPG Search( ) uses one bit of information toexpress, when the user makes an operation indicating the retrieval ofthe next PG during the period when the VOBs are being retrievedaccording to the PGC information included in the PGC StandardInformation, whether or not execution of interrupt processing for thisoperation is permitted.

PGC Standard Information-TopPG Search( ) or PGC StandardInformation-PrevPG Search( ) use one bit of information to express, whenthe user makes an operation indicating the retrieval of the top PG orprevious PG, respectively, during the period when the VOBs are beingretrieved according to the PGC information included in the PGC StandardInformation, whether or not execution of interrupt processing for theseoperations is permitted.

In the explanation of the PCI user operation limitation information, PCIStandard Information-Menu Call(Volume), PCI Standard Information-TopPGSearch( ) and PCI Standard Information-PrevPG Search( ) were describedas being explained later in the text, although they are in factbasically for the same functions as the PGC Standard Information-MenuCall(Volume), PGC Standard Information-TopPG Search( ) and PCI StandardInformation-PrevPG Search( ), except that they set whether functions,such as the calling of the volume menu or PG jumps, are permitted or notfor GOP units.

This completes the explanation of the data construction of the PGCinformation as shown in FIG. 11. The following is an explanation of howthe contents of each set of PGC information shown in FIG. 11 differ fromone another, with reference to FIG. 13.

In FIG. 13, the PGC standard information in PGC#1 is set so that ForwardScan is prohibited with VOB#9 being set as the VOB address information.The PGC standard information in PGC#2 is set so that Forward Scan ispermitted with VOB#1, #2, #3, #7 and #8 being set as the VOB addressinformation. The PGC standard information in PGC#3 is set so thatForward Scan is prohibited with VOB#1 and #4 being set as the VOBaddress information. The PGC standard information in PGC#5 is set sothat Forward Scan is prohibited with VOB#2 and #5 being set as the VOBaddress information. The PGC standard information in PGC#6 is set sothat Forward Scan is prohibited with VOB#3 and #5 being set as the VOBaddress information. The PGC standard information in PGC#7 is set sothat Forward Scan is prohibited with VOB#7 being set as the VOB addressinformation. Finally, the PGC standard information in PGC#8 is set sothat Forward Scan is prohibited with VOB#8 being set as the VOB addressinformation.

As explained above, the setting of VOB#1, #2, #3, #7 and #8 in the VOBposition information table of PGC information #2 is due to PGCinformation #2 being a reproduction route for a digest which is acollection of scenes showing tourist spots. The other sets of PGCinformation #1 and #5-#8 only have one or two VOBs set in their VOBposition information table, with this being due to these other sets ofPGC information being prepared separately for introducing the content ofthese VOBs individually or in pairs.

If attention is switched to user operations, it can be seen that PGCStandard Information-Forward Scan is permitted for PGC information #2but is prohibited for every other set of PGC information. This isbecause PGC information #2 is the digest version and so is set by thetitle developer to allow the user to view its content in a short periodof time using the fast forward reproduction function.

The remaining sets of PGC information are provided to give the detailsof various leisure activities and are to be leisurely viewed by theuser, who selects branch addresses by confirming items in menus.

(1.1.2) Logical Construction—Video Manager

The video manager includes video objects and a PGC managementinformation table, with its construction being almost the same as thatof the Video Title Set. The VOBs of the Video Manager differ from thatof the Video Title Set in that the Video Manager in two ways. Firstly,the VOB in the Video Title Set include video data, sub-picture data andaudio data for actual footage as shown in FIG. 5, while the VOB in theVideo Manager only contain a video pack and sub-picture pack and amanagement information pack for a background image for a menu. Secondly,the branch addresses of the branch-related commands in the PGCinformation and the Highlight Information of the Video Title Set do notexceed the range of the Video Title Set, while the branch-relatedcommands in the Video Manager have branch addresses for titles in avariety of Video Title Sets on the optical disc, so that they can crossover between Video Title Sets. The data construction of the VideoManager is shown in FIG. 32. As shown in FIG. 32, the “Video Manager” ismade up of “menu video objects”, a “menu PGC management informationtable” and a “title search pointer table”.

As its name suggests, the “menu video object” is a special VOB for thevolume menu. This is to say, it contains a sub-picture pack fordisplaying the volume menu and management information for performingreproduction control in accordance with cursor operations confirmationoperations for the menu. An example display of the volume menu is shownin FIG. 33. Here, the video object for the menu display has a pluralityof items numbered y611, y612, y613 and y616. These items are the titles“Hawaiian Islands Course”, “Guam Course” and “Saipan Course” which areincluded in the “Travel Mook”, with any one of these being selected bythe user. By making a confirmation operation for one of these items, auser indicated the title to be reproduced. The management informationpresent in this VOB includes a plurality of sets of HighlightInformation which for the title on the disc shown in FIG. 33. In thehighlight command field of these sets of Highlight Information,“TitlePlay” commands which have each Video Title Set and each title astheir branch addresses are stored.

The “Menu PGC management information table” is special PGC informationfor the volume menu and includes the storage position of the menu VOB sothat it can be read when a disc is inserted into the disc reproductiondevice. This PGC information is read by the disc reproduction deviceimmediately after the optical pickup has moved to the file area from thevolume management area when a disc has been inserted in the discreproduction device. By doing so, the volume menu is displayed on thescreen.

The “title search pointer table” is an index used to identify the videotitle set to which each title belongs and the title number of eachtitle.

(2.1) Outline of the Disc Reproduction Device

Now, a DVD player (reproduction device) for reproducing optical discs isdescribed with reference to the drawings. FIG. 14 shows the appearanceof DVD player 1, TV monitor 2, and remote controller 91.

DVD player 1 includes an optical disc drive in which an optical disc canbe inserted via the slot in the front.

Remote control receiving unit 92, also provided on the front of the DVDplayer, includes a light receiving device which receives infraredsignals transmitted by the remote controller 91. In response to theinfrared signals from the remote controller which represent a useroperation, remote control receiving unit 92 outputs an interrupt signalindicating that a key signal has been received.

A video output terminal and an audio output terminal are provided at therear of DVD player 1. AV cords are connected to these terminals to allowthe output of image signals to be reproduced by the DVD player to TVmonitor 2. The user can accordingly enjoy the images reproduced by theDVD player on a large-screen TV, such as a 33-inch or 35-inch model. Ascan be understood from the above description, DVD player 1 in thepresent embodiment is intended to be used as a household applianceconnected to TV monitor 2 and is not connected to a personal computer orthe like.

Remote controller 91 outputs infrared signals as codes when key padswhich are provided with springs under them on controller 91 are pressedby the user. Cylinder-shaped jog dial 810 which is 4-5 cm in diameter isalso provided on the controller. When the user rotates jog dial 810, therotation angle is converted into electric signal by a rotary encoder,with the electric signal then being output as infrared signals after A/Dconversion.

(2.2) Construction Elements of the Disc Reproduction Device

FIG. 15 is a block diagram showing the construction of the DVD playerused in the present embodiment. The DVD player includes optical discdrive 16, optical disc drive controlling unit 83, signal processing unit84, AV decoding unit 85, remote control receiving unit 92, and systemcontrolling unit 93. AV decoding unit 85 comprises signal separatingunit 86, video decoder 87, sub-picture decoder 88, audio decoder 89, andpicture mixing unit 90.

Optical disc drive 16 comprises a platter on which an optical disc isplaced and spindle motor 81 for rotating the inserted optical disc. Theplatter can be moved in and out of the cubic space provided for it inthe device by means of an eject mechanism which is not shown in thedrawing. The user places an optical disc on the platter when it has beenprojected forward outside the DVD player. After this, the platter ismoved back into the DVD player so as to load the optical disc.

Optical disc drive controlling unit 83 controls the optical pickup andoptical disc drive 16 including spindle motor 81. Specifically, opticaldisc drive controlling unit 83 adjusts the motor speed according to atrack position specified by system controlling unit 93, moves theoptical pickup by controlling the actuator of the pickup and, havingdetected a correct track by servo control, waits for a desired physicalsector before reading signals continuously starting from the desiredposition.

Signal processing unit 84 converts the signals read using the opticalpickup into digital data while performing various processes such asamplification, waveform shaping, conversion to binary, demodulation,error correction, etc. It then stores the processed data in buffermemory 94 (described later) in system controlling unit 93 in logicalblock units.

AV decoding unit 85 converts VOBs of digital data into the video signalsand audio signals.

Signal separating unit 86 receives the digital data transferred from thebuffer memory in units of logical blocks (packets), and classifies thedata into management information, moving picture data, sub-picture data,and audio data by identifying the stream ID and sub-stream ID of eachpacket. Signal separating unit 86 outputs the moving picture data tovideo decoder 87. Signal separating unit 86 outputs the managementinformation to system controlling unit 93. System controlling unit 93sends a valid channel number for each of the audio material and thesub-title material to signal separating unit 86. Signal separating unit86 outputs the audio data on the specified channel to audio decoder 89and the sub-picture data on the specified channel to sub-picture decoder88. The audio and sub-picture materials of other channels are discarded.

(2.2.1) Disc Reproduction Device . . . Construction of Signal SeparatingUnit 86

FIG. 16 is a block diagram showing the construction of signal separatingunit 86. As shown in the drawing, signal separating unit 86 comprisesMPEG decoder 120, sub-picture/audio separating unit 121, sub-pictureselecting unit 122, and audio selecting unit 123.

MPEG decoder 120 determines the types of packs transferred from thebuffer memory by checking the stream IDs and outputting the packets asfollows. If the stream ID is “1110 0000”, MPEG decoder 120 outputs thepacket to video decoder 87. If the stream ID is “1011 1101”, MPEGdecoder outputs to sub-picture/audio separating unit 121. Alternatively,if the stream ID is “1011 1111”, MPEG decoder 120 outputs to systemcontrolling unit 93.

Sub-picture/audio separating unit 121 outputs the packets input fromMPEG decoder 120 to sub-picture selecting unit 122 if their sub-streamID is “001* **** or to audio selecting unit 123 if their sub-stream IDis “1010 0***”. As a result, each set of sub-picture data and audio datais appropriately output to either sub-picture selecting unit 122 oraudio selecting unit 123.

Sub-picture selecting unit 122 outputs the sub-picture data on thechannel number specified by system controlling unit 93 to sub-picturedecoder 88 and discards the rest of the sub-picture data. Suppose, inFIG. 6, sub-picture materials for channels A and B are respectivelyEnglish and French subtitles. If, in this case, channel A is specified,sub-picture selecting unit 122 outputs the sub-picture data on channel Ato sub-picture decoder 88 so that sub-picture decoder 88 decodes onlythe English subtitles.

Audio selecting unit 123 outputs the audio data on the channel numberspecified by system controlling unit 93 to audio decoder 89 and discardsthe rest of the audio data. Suppose, in FIG. 5, the audio material onchannels A, B, and C are English, French, and Japanese soundtracks,respectively. If, if this case, channel A is specified, audio selectingunit 123 outputs the audio data on channel A to audio decoder 89 so thataudio decoder 89 decodes only the English audio data.

Video decoder 87 decodes and decompresses the moving picture data sentfrom signal separating unit 86, before outputting the data to picturemixing unit 90 as digital video signals.

Sub-picture decoder 88 decodes and decompresses the sub-picture datasent from signal separating unit 86 if the sub-picture data is imagedata compressed with run length compression and outputs the sub-picturedata to picture mixing unit 90 in the same format as the video signals.Here, the color palette of the image data can be changed according toinstructions from system controlling unit 93. Therefore, if the imagedata is provided with a plurality of items and the user moves the cursorbetween these items, system controlling 93 instructs sub-picture decoder88 to change the color palette (or change the color) of the image data.Such instructions for changing color are output based on the item colorinformation recorded in the Highlight Information. According to theinstruction, the item changes its color to the selection color or theconfirmation color. The selection color indicates the position of thecursor.

The description of the construction of DVD decoder 1 continues withreference to FIG. 15. Audio decoder 89 decodes and extends the audiodata sent from signal separating unit 86 before outputting digital audiosignals.

Picture mixing unit 90 outputs picture signals after mixing the outputsfrom video decoder 87 and sub-picture decoder 88 according to the ratiospecified by system controlling unit 93. The mixture ratio is determinedbased on the contrast given in the item color information in theHighlight Information. The mixture ratio can be changed for each GOPunit. The picture signals are converted to analog signals, then inputinto TV monitor 2.

(2.2.2) Disc Reproduction Device . . . Construction of SystemControlling Unit 93

System controlling unit 93 controls the entire DVD player 1 and iscomposed as shown in FIG. 17. System controlling unit 93 includes buffermemory 94, management information pack buffer 95, embedded processor 96,PGC information buffer 31, Highlight Information buffer 32, and PCI useroperation limitation information buffer 33.

Embedded processor 96 includes a ROM storing a control program for allof DVD player 1, a work memory and a CPU. The CPU includes a fetchingunit for sequentially fetching addition/subtraction commands and branchcommands from Highlight Information buffer 32, a command buffer forstoring the fetched addition/subtraction commands and branch commands, adecoding unit for decoding operation codes and operands stored in thecommand buffer, a calculator for performing operations specified in theoperation codes by using the values stored in general-purpose registersand immediate values stored in the instruction buffer, and buses fortransferring the operation results and immediate values specified inoperands to general-purpose registers.

Buffer memory 94 stores data for which the processes such asamplification, waveform shaping, conversion to binary, demodulation,error correction, have been performed. From this buffer memory 94,system controlling unit 93 transfers the Video Title Set managementinformation to another buffer which is not shown in the drawing and VOBsto signal separating unit 86 in pack units. Signal separating unit 86sends back the management information pack to system controlling unit93.

Management information pack buffer 95 stores the management informationpack sent back from signal separating unit 86.

Embedded processor 96 instructs management information pack buffer 95 tooverwrite the Highlight Information or only the highlight command storedin Highlight Information buffer 32 by referring to a flag indicating achange from the previous VOB unit, the flag being included in thehighlight standard information in the stored management informationpack.

PGC information buffer 31 stores the PGC information which is currentlyselected. Here, PGC information buffer 31 includes a PGC user operationlimitation information buffer for storing PGC user operation limitationinformation. The format of this PGC user operation limitationinformation is shown in FIG. 12. When the user requests fast forward orrewind by operating the remote controller, embedded processor 96 refersto each set of PGC Standard Information (Backward Scan( ) to PrevPGSearch( ).TopPG Search( )) of the PGC user operation limitationinformation to judge whether to execute fast forward/rewind.

Highlight Information buffer 32 is a buffer whose area is divided into aplurality of small areas. Highlight Information buffer 32 stores thisHighlight Information whose format is shown in FIG. 9B. Embeddedprocessor 96 reads the cursor position, selection color, confirmationcolor, and highlight command from Highlight Information buffer 32. TheHighlight Information stored in Highlight Information buffer 32 isoverwritten by the Highlight Information stored in managementinformation pack buffer 95 according to instructions from the embeddedprocessor 96. That is, only the Highlight Information necessary for thesection of the system stream which is currently being reproduced isstored in Highlight Information buffer 32, even though a considerablenumber of management information packs are interleaved in the systemstream.

PCI user operation limitation information buffer 33 stores PCI useroperation limitation information which is included in managementinformation packs. The PCI user operation limitation information newlystored in management information pack buffer 95 is also stored in PCIuser operation limitation information buffer 33 by embedded processor96.

Channel register 99 stores an audio channel number, sub-picture channelnumber and angle position number. Each of these numbers is incrementedby one each time the user depresses the audio switch key, the angleswitch key or the sub-picture switch key. As a result, a channel isswitched each time any of these keys is pressed. For audio data, thechannel is switched from A to B, from B to C, and from C to A. Forsub-picture data, the channel is switched from A to B and from B to A.For angle position data, the channel is switched from A to B, from B toC, and from C to A.

In this way, the numbers stored in channel register 99 corresponding tothe channels are cyclically incremented each time any of the angleswitch key, sub-picture switch key, and audio switch key is pressed. Ofthese, numbers for audio data and sub-picture data are output to systemdecoder 86 as channel control signals.

The ROM included in embedded processor 96 stores a control program forprocessing interrupts which the user requests by pressing keys on remotecontroller 91. The flowcharts of FIGS. 21A and 21B show the keyinterrupt type determination process by system controlling unit 93.

In the flowcharts of FIGS. 21A and 21B, interrupt processing isperformed according to the operation of remote controller 91. FIG. 18shows the panel of remote controller 91. As shown in the drawing, remotecontroller 91 includes angle switch key 801, sub-picture switch key 802,Volume Menu key 803, audio switch key 804, PG jump key 805 (Next PG,Prev PG, and Top PG), Pause key 807, jog dial 810. If any of these keysis pressed, the control moves to any of steps 152 to 160 in theflowcharts. As shown in the drawings, the process includes a series ofjudgement steps. If angle switch key 801 is pressed, it is judged as“Yes” at step 153 and control moves to the interrupt processing shown inFIG. 24; Volume Menu key 803 to FIG. 26; Pause key 807 to FIG. 25; PGjump key 805 to FIG. 27; jog dial 810 to FIG. 22.

If any of up, down, left, and right cursor keys is pressed, it is judgedas “Yes” at step 159 and control moves to step 202. At step 202, it isjudged whether a corresponding cursor move is permitted by referring tothe PGC user operation limitation information. If permitted, the cursoris moved between items by using item information at step 200. Here, ifthe Enter key is pressed, it is judged as “Yes” at step 160. Next, atstep 203, it is judged whether a confirmation operation is permitted. Ifpermitted, at step 201, a branch command or an addition/subtractioncommand is read from the highlight command field of the item informationof the present item number and the command is executed.

Seven types of interrupts are processed in the present embodiment asshown in FIGS. 22 to 27.

FIG. 22 shows interrupt processing for fast forward/rewind key and jogdial 810. At step 170, “Forward Scan( )” and “Backward Scan( )” of PCIStandard Information and PGC Standard Information are referred to. If atleast one of them is “not permitted”, control returns without anyexecutions. If both of them are “permit”, the top I-picture address inthe management information pack address is read at step 171, and theI-picture of this address is read by video decoder 87 at step 172. Atstep 176, the direction of optical pickup is determined according to thetype of pressed key or the rotation direction of the jog dial. At step173, the skip amount is determined out of amounts 1-15, 20, 60, 120, and240 according to the type of pressed key or the rotation amount of thejog dial. At step 174, the DSI of the management information pack storedin management information pack buffer 95 is referred to and themanagement information pack address related to the rotation directionand skip amount is obtained from the high-speed search informationtable. Then, system controlling unit 93 instructs optical disc drivecontrolling unit 83 to move the optical pickup to the obtainedmanagement information pack address at step 175.

FIG. 23 shows interrupt processing for the Audio/sub-channel switch key.If the Audio switch key has been pressed, at step 161, it is judgedwhether at least one of “Audio Stream Change( )” in the PCI StandardInformation and PGC Standard Information is “not permit.” If theSub-picture switch key has been pressed, at step 161, it is judgedwhether at least one of “Sub-Picture Stream Change( )” of PCI StandardInformation and PGC Standard Information is “not permit.”

If at least one of PCI Standard Information and PGC Standard Informationis “not permit,” control returns without any executions. If both of themare “permit,” control moves to step 162. At step 162, the channel numberof audio data or sub-picture data in the channel register is incrementedand the incremented channel number “i” is fetched. At step 163, signalseparating unit 86 is instructed to decode the packs of the fetchedchannel number. With this instruction, decoding target changes betweenaudio channels A to C and sub-picture channels A and B.

FIG. 24 shows interrupt processing for Angle switch key. When the Angleswitch key has been pressed, it is judged at step 140 whether at leastone of “Angle Change( )” of PCI Standard Information and PGC StandardInformation is “not permit.”

If at least one of PCI Standard Information and PGC Standard Informationis “not permit,” control returns without any executions. If both of themare “permit,” control moves to step 141. At step 141, the angle positionnumber in the channel register is incremented and the incremented angleposition number is fetched. At step 142, management pack address ofangle cell with fetched angle position number is read from DSI angleinformation. Then, system controlling unit 93 instructs optical discdrive controlling unit 83 to move the optical pickup to the obtainedmanagement information pack address at step 143.

FIG. 25 shows interrupt processing for Pause key. If the Pause key hasbeen pressed, it is judged whether at least one of “Pause ( )” of PCIStandard information and PGC Standard Information is “not permit” atstep 181.

If at least one of PCI Standard Information and PGC Standard Informationis “not permit,” control returns without any executions. If both of themare “permit,” control moves to step 185. At step 185, optical disc drivecontrolling unit 83 is stopped, and an underflow is generated in thebuffer in the video decoder. At step 186, the video decoder maintainsfreeze state. As a result, the screen displays a still image.

FIG. 26 shows interrupt processing for VolumeMenu key. If the VolumeMenukey has been pressed, it is judged whether at least one of “Menu Call()” of PCI Standard Information and PGC Standard Information is “notpermit” at step 210.

If at least one of PCI Standard Information and PGC Standard Informationis “not permit,” control returns without any executions. If both of themare “permit,” control moves to step 211. At step 211, the address of thevideo manager is obtained from the file system management information.At step 212, the video manager file is opened and the menu PGCinformation is stored in the PGC information buffer. At step 213, menuVOBs are read sequentially according to the menu PGC information, themenu images are displayed on the screen and Highlight Information of themenu VOB is stored in the Highlight Information buffer. At step 214, itis judged whether the remote control receiving unit has received asignal for any of the cursor keys, Enter key, and numeral keys. If sucha signal has been received, processing is performed according to theHighlight Information of the menu VOB. This processing is shown in FIG.21B.

FIG. 27 shows interrupt processing for Next PG, Prev PG, and Top PGkeys. If a jump key has been pressed, it is judged whether at least oneof “PG Search( )” of PCI Standard Information and PGC StandardInformation is “not permit” at step 191.

If at least one of PCI Standard Information and PGC Standard Informationis “not permit,” control returns without any executions. If both of themare “permit,” control moves to step 192. At step 192, the jump key isidentified. Next, the PG number of PG where the optical pickup currentlystays is obtained from the PG map of PGC information, and VOB number #jrelated to the PG number is obtained from the PG map of PGC information.At step 193, VOB address information of VOB number #j is sent to opticaldisc drive controlling unit 83.

(2.2.2.1) Specification of Entry Program Chain by System ControllingUnit 93

The following is a description of the operation of DVD player 1 withreference to FIGS. 19A and 19B. FIGS. 19A and 19B show a flowchartshowing the process steps of system controlling unit 93.

In order to insert an optical disc, the user presses the eject button onthe front side of DVD player 1 and places the optical disc on theejected platter. Then, the platter, with the optical disc, moves intothe DVD player and the optical disc is loaded into the DVD player.

At step 121, system controlling unit 93 is in a wait state judgingwhether an optical disc has been inserted. On receiving notificationfrom an optical sensor that an optical disc has been inserted, systemcontrolling unit 93 controls optical disc drive controlling unit 83 andsignal processing unit 84 so that the rotation of the disc is controlledwhile optical pickup is placed in the lead-in area. The disc rotation isstabilized while optical pickup is placed in the lead-in area. After therotation is stabilized, the optical pickup is moved from the lead-inarea toward the outer periphery and the volume management area is read.Then, according to the information read from the volume management area,the Video Manager is read (step 122). System controlling unit 93calculates the address of the program chain of the volume menu byreferring to the menu program chain management information in the VideoManager, reproduces the program chain and then stores it in PGCinformation buffer 31. Next, system controlling unit 93 refers to thePGC information stored in the buffer and identifies the VOB to bereproduced, before calculating its address. System controlling unit 93outputs control signals to optical disc drive controlling unit 83 andsignal processing unit 84. Next, the VOB is fetched from the opticaldisc and reproduced, displaying the volume menu as shown in FIG. 33 onTV monitor 2 (step 123).

If the user selects an item in the menu and performs the confirmationoperation for the item, system controlling unit 93 executes the command“PlayTitle” specifying the title number which is set as a highlightcommand corresponding to the title (step 125). The operation of systemcontrolling unit 93 in item selection/confirmation is described indetail in the succeeding section.

The command “PlayTitle” instructs system controlling unit 93 to refer tothe title search pointer table of the video manager to determine theVideo Title Set (VTS) and the VTS title number. Then, system controllingunit 93 outputs control signals to optical disc drive controlling unit83 and signal processing unit 84, reproduces the Video Title Setmanagement information of the determined video title, before fetchingthe Video Title Set unit title search pointer table of this information(step 126).

System controlling unit 93 determines the PGC information of the firstprogram chain in the title by referring to the fetched Video Title Setunit title search pointer table. Then, system controlling unit 93outputs control signals to optical disc drive controlling unit 83 andsignal processing unit 84, reproduces the determined PGC information,and stores the information in PGC information buffer 31. The PGCinformation of the volume menu is overwritten by the PGC information.System controlling unit 93 determines the video object to be reproducedand its address by referring to the stored PGC information, outputscontrol signals to optical disc drive controlling unit 83 and signalprocessing unit 84, and reproduces the determined video object.

After this, system controlling unit 93 determines and reproduces videoobjects in order according to the stored PGC information. Systemcontrolling unit 93 determines the next PGC information by referring tothe PGC connection information of the current PGC information when itcompletes reproducing the last video object specified in the current PGCinformation. Next, system controlling unit 93 discards the current PGCinformation and stores the next PGC information to continue thereproduction (step 128).

(2.2.2.2) Operation Example 1 . . . Reproduction Control for Video TitleSet v1

FIG. 31A and FIG. 31B shows the operation of the examples shown in FIGS.10A to 10C and FIG. 13 under control of the FIG. 20 flowchart. ArrowsR100, R101, R102, . . . indicate storage of PGC information in PGCinformation buffer 31 at step 127 and other steps. Arrow R100 indicatesstorage of PGC information #1 shown in FIG. 13A in PGC informationbuffer 31.

Arrow R101 indicates that PGC information #2 shown in FIG. 13A is storedin PGC information buffer 31 when the highlight command in VOB#9 isexecuted at step 201. Arrow R102 indicates that PGC information #3 shownin FIG. 13A is stored in PGC information buffer 31 when the highlightcommand in VOB#9 is executed at step 201.

Broken arrows K100, K101, K102, . . . indicate the movement of theoptical pickup to the VOB record start position. Arrow K101 indicatesthat the optical pickup moves to VOB#1 record start position when step134 is executed for VOB address information of VOB#1 in PGC information#2. Arrow K102 indicates that the optical pickup moves to VOB#2 recordstart position when step 134 is executed for VOB address information ofVOB#2 in PGC information #2.

Arrow K106 indicates that the optical pickup moves to VOB#1 record startposition when step 134 is executed for VOB address information of VOB#1in PGC information #3.

Outline arrows F101, F102, F103, . . . indicate the scan with theoptical pickup of VOB record area at steps 135 and 136. Arrow F101indicates that VOB#9 is scanned by optical pickup when steps 135 and 136are repeatedly executed for the VOB address table. Arrow F102 indicatesthat VOB#1 is scanned by optical pickup when steps 135 and 136 arerepeatedly executed for the VOB address table. Arrow F103 indicates thatVOB#2 is scanned by optical pickup when steps 135 and 136 are repeatedlyexecuted for the VOB address table.

Now, the software control performed by system controlling unit 93 forVideo Title Set v1 shown in FIG. 2B is described with reference to theflowcharts of FIGS. 20-35.

Suppose the user selects the “Hawaiian Islands Course” of “Travel Mook”.With this selection, PGC information buffer 31 stores PGC information#1. As shown in FIG. 13A, the VOB address information of PGC information#1 stores VOB#9 record position. At steps 133 and 134, systemcontrolling unit 93 reads the VOB address information of VOB#9 from theVOB address information table of PGC information #1, and instructsoptical disc drive controlling unit 83 to access the first position ofthe record area according to the VOB address information. After theoptical pickup moves to the start of the record area under control ofoptical pickup controlling unit 83, system controlling unit 93 instructsoptical pickup controlling unit 83 to read data starting from the startposition at step 136. Optical pickup controlling unit 83 drives theoptical disc to rotate according to the instruction. This instruction isrepeatedly executed at step 135. When this happens, packs of the VOB areread sequentially starting from the start position of the record area.

With this repetition, a menu is displayed on the screen including“Recommended Course and ” Choose Your Own Itinerary” for GOP #100 to GOP#200 as shown in FIG. 10C.

The management information packs of these GOPs include item information#1 and item information #2 corresponding to the items. Morespecifically, The highlight command fields of item information #1 anditem information #2 respectively include “Link PGC2” branching to PGCinformation #2 and “Link PGC3” branching to PGC information #3. Havingnot determined where to go in a upcoming long vacation, the user wantsto find a good place for a tour. The user presses a numeral key on theremote controller corresponding to “Recommended Course” in the menu.Meanwhile, system controlling unit 93 monitors interrupt signals sentfrom remote control receiving unit 92. When the above press is detected,it is judged as “Yes” at step 137, and control moves to the flowchartshown in FIG. 21.

As a numeral key has been pressed, it is judged as “No” at step 152through step 157, and judged as “Yes” at step 158. Then, it is confirmedthat “Item Activate( )” of PGC Standard Information is “permit” at step203. A command stored in the highlight command field of item information#1 is read and executed at step 201. Since the command is a branchcommand, control branches to another program chain according to theflowchart of FIG. 19C.

Now, this branch is described with reference to FIG. 19C. FIG. 19C showsa flowchart of a process executed by branch commands.

At step 71, a program chain number written in the branch target field ofthe command is read. At step 72, the logical block equal to the startposition of PGC information #2 in the PGC management information iscalculated by referring to the first address of the PGC managementinformation written in the Video Title Set management table in the videomanager. At step 73, optical disc drive controlling unit 83 moves theoptical pickup to the calculated logical block. At step 74, PGCinformation #2 read from the logical block through optical pickup andoptical disc drive controlling unit 83 is stored in PGC informationbuffer 31. The PGC information is processed as shown in the flowchart ofFIG. 20.

After the branch to PGC information #2, the VOB address information isread from the VOB address information table of PGC information #2 shownin FIG. 13A at step 133. Then, at step 134, system controlling unit 93instructs optical disc drive controlling unit 83 to access the recordingstart position of VOB#1. When the above step is executed, the opticalpickup moves to the start position of the VOB, and system controllingunit 93 instructs optical disc drive controlling unit 83 to sequentiallyread logical blocks of the optical disc. This allows the reproductiondevice to sequentially read packs of VOB#1 starting from the recordingstart position. As a result, packs GOP #00 through GOP #200 shown inFIG. 13A are separated by system decoder 86, decoded and converted intoimage signals by video decoder 87, and mixed with sub-pictures bypicture mixing unit 90. When this happens, advertisements for a touroperator and an airline are displayed on the screen for several minutes.FIG. 28 shows an advertisement as displayed on the screen.

Suppose the user operates jog dial 810 intending to forward the imagesat high speed. This operation leads the reproduction device to step 137of FIG. 20. Since it is judged as “Yes” at step 137, control moves tothe flowchart of FIG. 21. In the flowchart, it is judged as “Yes” atstep 152, then, control moves to step 170 of FIG. 22. The flowchart ofFIG. 22 shows the procedure for an interrupt of fast forward/rewindexecuted by system controlling unit 93. System controlling unit 93refers to the user operation limitation information of PGC StandardInformation. Here, “Forward Scan( )” of PGC Standard Information is setas “permit.” However, “Forward Scan( )” of PCI Standard Information isset as “not permit” as shown in FIG. 13A. Therefore, it is judged as“Yes” at step 170, and control moves to step 135 of FIG. 20. As aresult, the images are reproduced without fast forward even if the useroperates jog dial 810, and the advertisements are displayed on thescreen from start to end.

After the advertisements, packs GOP #250 through GOP #450 of VOB#1 areseparated by system decoder 86, decoded and converted into image signalsby video decoder 87, and mixed with sub-pictures by picture mixing unit90. When this happens, footage of attractive beaches, which could showyoung people bathing in the sun, playing into the waves, playing beachvolleyball, talking each other with surfboards under their arms and thelike for several minutes.

Suppose the user operates jog dial 810 intending to forward the imagesat high speed. This operation leads the reproduction device to step 137of FIG. 20. Since it is judged as “Yes” at step 137, control moves tothe flowchart of FIG. 21. In the flowchart, it is judged as “Yes” atstep 152, then, control moves to step 170 of FIG. 22. System controllingunit 93 refers to “Forward Scan( )” of PGC Standard Information and PCIStandard Information. Here, since “Forward Scan( )” of both pieces ofinformation are set as “permit,” steps 171 and 172 are executed. First,the initial I-picture address in the management information pack addressis read. Then, video decoder 87 reads only I-picture with the readaddress. Then, control moves to step 176, then, to step 173. In thesesteps, the direction of the optical pickup and skip amount aredetermined from the rotation direction and rotation amount of jog dial810. At step 174, the management information pack address related to therotation direction and skip amount is obtained from the high-speedsearch information table. Then, system controlling unit 93 instructsoptical pickup controlling unit 83 to move forward the optical pickup bythe calculated skip amount at step 175. These steps 171 to 175 arerepeated until jog dial 810 stops rotating. In the repetition, theoptical pickup skips integer multiples of GOP, reads managementinformation packs by skipping several packs, and I-pictures aredisplayed on the screen with ratio of one to about 15.

After the reproduction of VOB#1 with fast forward, control moves to step132. At steps 132 and 133, system controlling unit 93 reads VOB addressinformation of VOB#2 written next to VOB#1 in the VOB addressinformation table. At steps 134 to 136, system controlling unit 93instructs optical disc drive controlling unit 83 to read data betweenthe logical blocks written in the VOB address information. By repeatingthe instruction as many as the number of blocks in the VOB addressinformation at step 135, VOBs are read in units of packs from the startposition of the record area. When this happens, packs GOP #00 throughGOP #200 of VOB#2 as shown in FIG. 10A are decoded and converted intoimage signals by video decoder 87, and mixed with sub-pictures bypicture mixing unit 90. As a result, shots showing the facilities athigh class hotel A, such as the VIP room, lobby, guest room, outsidepool, etc. are displayed on the screen.

When the above process for VOB#2 is repeated also for VOB#7 and VOB#8according to the VOB address information, pieces of VOB addressinformation are read in order of the VOB address information table, andoptical disc drive controlling unit 83 is instructed to move the opticalpickup to the recording start position of each VOB as indicated byarrows K103, K104, and K105. Then, each VOB is sequentially read asindicated by arrows F104, F105, and F106.

As VOB#2 is read, packs GOP #250 to GOP #450 are converted into imagesignals and shots introducing room rates and check-in/check-outprocedure are displayed on the screen for about 25 seconds. As VOB#7 isread, shots introducing diving precautions and emergency procedures arcdisplayed for several minutes. As VOB#8 is read, shots of a city withprecautions to be taken around town and contacts in case of emergencyare displayed for several minutes.

After the reproduction of VOB#8 completes, control returns to theflowchart of FIG. 19A from FIG. 20, then moves to step 81 of FIG. 19B.

The flowchart of FIG. 19B shows the branch process with the connectioninformation. At step 81, the program chain number written in theconnection information is read. Suppose PGC information #1 is specifiedas the branch target. At step 82, the logical block equal to the startposition of PGC information #1 in the PGC management information tableis calculated by referring to the first address of the PGC managementinformation table written in the Video Title Set management informationin the video manager. At step 83, optical disc drive controlling unit 83moves the optical pickup to the calculated logical block. At step 84,PGC information #1 read from the logical block through optical pickupand optical disc drive controlling unit 83 is stored in PGC informationbuffer 31. The PGC information is processed as shown in the flowchart ofFIG. 20 and program chain reproduction is performed according to newlystored PGC information #1. System controlling unit 93 instructs opticaldisc drive controlling unit 83 to access the first position of therecord area of VOB#9 again according to the VOB address informationtable of PGC information #1. At steps 135 and 136, system controllingunit 93 instructs optical pickup controlling unit 83 to sequentiallyread data stored in the logical block. When this happens, packs of VOB#9are read from the start position of the record area starting from therecord area.

With this reading, a menu including “Recommended Course” and “ChooseYour Own Itinerary” is displayed on the screen again. The managementinformation packs of these GOPs include item information #1 and iteminformation #2 corresponding to the items. More specifically, Thehighlight command fields of item information #1 and item information #2respectively include “Link PGC#2” branching to PGC information #2 and“Link PGC#3” branching to PGC information #3. The user presses a keycorresponding to “Choose Your Own Itinerary” with a resolve to selectthe Hawaiian Islands for the tour destination. Meanwhile, systemcontrolling unit 93 monitors interrupt signals sent from remote controlreceiving unit 92. When the above press is detected, it is judged as“Yes” at step 137, and control moves to the flowchart shown in FIG. 21.

It is judged as “No” at steps 152 through 157, and judged as “Yes” atstep 158. Then, a command stored in the Highlight Command field of iteminformation #2 is read and executed at step 201. Since the command is abranch command, PGC information #3 specified as the branch target isstored in the buffer and the branch is executed according to the programchain. This allows the reproduction device to branch from the middle ofreproduction of a VOB to PGC information #3.

System controlling unit 93 reads the VOB address information of VOB#1from the VOB address information table of PGC information #3, andinstructs optical disc drive controlling unit 83 to sequentially readdata from the logical block of the record area specified by VOB addressinformation. When this happens, packs of the VOB are read sequentiallystarting from the start position of the record area. Packs GOP #00 to#200 as shown in FIG. 10A are converted into image signals and mixedwith sub-pictures by picture mixing unit 90. Then, advertisements of atravel agency and an airline are displayed on the screen for severalminutes.

This time, the user presses fast forward key, not interested in theimages. Here, since “Forward Scan( )” of both PCI Standard Informationand PGC Standard Information are set as “not permit,” it is judged as“Yes” at step 170, and control moves to step 135 of FIG. 20. As aresult, the images are reproduced without fast forward even if the userpresses fast forward key, and the advertisements are displayed on thescreen from start to end.

As shown in FIG. 31A and FIG. 31B, VOB#1 is read as indicated by arrowF102 and packs GOP #250 through GOP #450 of VOB#1 are separated bysystem decoder 86, decoded and converted into image signals by videodecoder 87, and mixed with sub-pictures by picture mixing unit 90. Whenthis happens, shots introducing attractive beaches such as young peoplebathing in the sun, playing in the waves, playing beach volleyball,talking each other with surfboards under their arms, etc. for severalminutes.

After all the packs in VOB#1 are read, the VOB address information ofVOB#4, which is recognized as the next VOB, is read from the VOB addressinformation table. At steps 134 to 136, data between the logical blockswritten in the VOB address information of VOB#4 is read. The userpresses fast forward key, not interested in the images.

Here, since “Forward Scan( )” of PGC Standard Information for PGCinformation #4 is set as “not permit,” it is judged as “Yes” at step170, and control moves to step 135 of FIG. 20. As a result, the imagesare reproduced without fast forward even if the user presses fastforward key, and the images are displayed on the screen from start toend.

As VOB#4 is reproduced next, packs GOP #100 through #200 are reproducedand a menu including two items, namely, “Deluxe Course” and “BudgetCourse”, is displayed on the screen. These two items are respectivelyrelated to item information #1 and item information #2. Item information#1 includes a command “LinkPGC#5” for changing the reproduction route,and item information #2 a command “LinkPGC#6.” The user, having beeninterested in the deluxe hotels and been resolved to stay at one ofthese hotels, presses a numeral key corresponding to “Deluxe Course”.

This key operation allows the reproduction device to execute the commandwritten in the highlight command field. This command allows thereproduction device to store PGC information #5, which is specified asthe branch target, into a buffer and operate according to the PGCinformation. The user might have missed the menu if he/she could use thefast forward function. However, as the PGC information of the menuprohibits the fast forward, the user can look at the menu.

This leads the reproduction device to branch from the middle of VOB#4 toPGC information #5. After the branch, as indicated by arrow K108 in FIG.31B, the VOB address information table of PGC information #5 instructsoptical pickup controlling unit 83 to drive the optical disc to rotateso that packs are read starting from the start position of the VOB#2record area. When this happens, packs of the VOB are read sequentiallystarting from the start position of the record area. As a result, packsGOP #00 through GOP #200 of VOB#2 shown in FIG. 13A are converted intoimage signals, and shots introducing facilities at high class hotel Asuch as a VIP room, lobby, guest room, outside pool, etc. are displayedon the screen.

The user presses fast forward key, not interested in the images. Here,since “Forward Scan( )” of PGC Standard Information for PGC information#6 is set as “not permit,” it is judged as “Yes” at step 170, andcontrol moves to step 135, of FIG. 20. As a result, the images arereproduced without fast forward even if the user presses fast forwardkey, and the images are displayed on the screen from start to end.

As VOB#2 is read, packs GOP #250 to GOP #450 are converted into imagesignals and detailed information on hotel A such as room rates,check-in/check-out procedure, service charges, tips, manner, etc. isdisplayed on the screen. Since high class hotel A is proud of itstraditions and has high standards, guests are supposed to observe formalrules of etiquette. Therefore, the tour operator will want the user toread the information and to observe their guidelines. For this purpose,PGC information #5 specifies fast forward as “not permit.” This leadsthe user to look at the information.

At step 135, data is read as many times as the number of blocks in theVOB address information. Then, control moves to step 132. At steps 132and 133, system controlling unit 93 reads VOB address information ofVOB#5, namely, a next VOB, in the VOB address information table. Atsteps 134 to 136, data between the logical blocks written in the VOBaddress information is read.

Optical pickup controlling unit 83 is instructed to move the opticalpickup to the start position of the VOB#9 record area as indicated byarrow K110, and packs of VOB#9 are read sequentially as indicated byarrow F108.

As packs GOP #100 through GOP #200 of VOB#9 are reproduced, a menu isdisplayed on the screen including items “Diving” and “City Sightseeing”.The two items respectively correspond to item information #1 and iteminformation #2. Item information #1 and item information #2 respectivelyinclude commands for branching to PGC7 and PGC8.

Suppose the user has a diving license and plans to go to diving in thecoming holidays. The user presses a numeral key corresponding to“Diving”.

This key operation allows the reproduction device to execute the commandwritten in the highlight command field. This command allows thereproduction device to store PGC information #7, which is specified asthe branch target, into a buffer and operate according to the PGCinformation.

This leads the reproduction device to branch from the middle of VOB#9 toPGC information #7. After the branch, as indicated in FIG. 31, packs GOP#100 through GOP #200 of VOB#7 are converted into image signalsaccording to the VOB address information table of PGC information #7,and shots introducing coral reefs and tropical fish are displayed on thescreen for several minutes.

Packs GOP #300 through GOP #400 of VOB#7 as shown in FIG. 10C areseparated by system decoder 86, decoded and converted into image signalsby video decoder 87, and mixed with sub-pictures by picture mixing unit90. When this happens, shots introducing diving precautions andemergency procedures are displayed on the screen for several minutes.The tour operator desires the user to read the cautions. For thispurpose, PGC information #7 specifies fast forward as “not permit.” Thisleads the user to look at the information even if he/she presses thefast forward key.

<Operation Example of “Demonstration”>

Now, an operation example of “Demonstration”, for which “controlconstruction with two sides” is used, is described with reference toFIG. 34. In FIG. 34, demonstration item y616 is connected by arrow R201to PGC information #53. This indicates that the entry program chain ofthe demonstration is PGC information #53. PGC information #53 isconnected by arrows K106 and K107 to VOB#1 and VOB#4 respectively. Thisindicates that the VOB address information table of PGC information #53specifies the same continuous reproduction of VOB#1 and VOB#4 as PGCinformation #3 specifies.

Also, in the drawing, PGC information #55 is connected by arrows K108and K110 to VOB#2 and VOB#5 respectively. This indicates that the VOBaddress information table of PGC information #55 specifies the samecontinuous reproduction of VOB#2 and VOB#5 as PGC information #5specifies.

As a result, the reproduction is controlled according to PGC information#53 and PGC information #55, and the images of “Choose Your OwnItinerary” and “Deluxe Course” are displayed on the screen insuccession.

Here, it is supposed that “Demonstration” is executed in front of atravel agency by its staff to demonstrate the software title topassers-by.

The PGC user operation limitation information of PGC information #53 isdifferent from that of PGC information #3. FIG. 35 shows a descriptionin the PGC user operation limitation information of PGC information #53.In the drawing, PGC Standard Information “Forward Scan( )” is set as“not permit” to prohibit passers-by from performing the fast forward.With such setting, passers-by are forced to see the images and hear thenarration of the demonstration.

On the other hand, PGC Standard Information “Backward Scan( )” is set as“permit” to allow the passers-by to perform the rewind. With suchsetting, a passer-by can see the images and hear the narration of thedemonstration again and again if he/she is interested in the piece.

PGC Standard Information “Pause Scan( )” is also set as “permit” toallow the passers-by to perform the pause. With such a setting, apasser-by can watch a still image of the demonstration if he/she isinterested in the image.

Please pay attention to PGC Standard Information “Upper Item Select( )”through “Item Activate( )” shown in the drawing.

“Upper Item Select( )” through “Left Item Select( )” are all set as“permit,” and only “Item Activate( )” is set as “not permit.” Thissetting is intended to impress passers-by with the interactiveoperation.

PGC Standard Information “Item Activate( )” is set as “not permit” toprohibit passers-by from using branches which are executed by highlightcommands. However, the VOB address information table of the PGC commandtable includes command “Link PGC#55” which instructs the reproductiondevice to branch to PGC information #55 after reading all VOBs with VOBaddress information (a command which instructs the reproduction deviceto execute a process after reading all VOBs is called a post-processingcommand). As a result, the reproduction device automatically branches toPGC information #55. When this happens, PGC information #55 overwritesPGC information #53 stored in PGC information buffer 31. Thereproduction device reads VOB#2 and VOB#5 in succession according to PGCinformation #55.

In this way, the demonstration displays shots and sub-pictures which areincluded in the Hawaiian Islands course but partly prohibits thebranches.

Suppose a passer-by takes remote controller 91 and presses a cursor keywatching a menu displayed on the screen, while DVD player 1 currentlyreproduces VOB#1 or VOB#4.

Meanwhile, at steps 135 through 137, system controlling unit 93 monitorsthe reception of an interrupt signal sent from remote control receivingunit 92 while logical blocks are repeatedly read. Now, systemcontrolling unit 93 detects an interrupt generated by the passer-by. Atstep 137, it is judged as “Yes” and control moves to the flowcharts ofFIGS. 21A and 21B.

At steps 152 through 157, it is judged as “No,” and judged as “Yes” atstep 159 since a cursor key has been pressed. At step 202, PGC StandardInformation “Upper Item Select( )” through “Left Item Select( )” arereferred to. Since they are all set as “permit,” control moves to step200. At step 200, color change is specified to sub-picture decoder 88and the cursor is moved.

Being able to move the cursor about on the screen at his/her own willusually arouse the interest of a passer-by. The passer-by presses theEnter key while the cursor stays at “Budget Course”.

At steps 135 through 137, system controlling unit 93 monitors thereception of an interrupt signal sent from remote control receiving unit92 while logical blocks are repeatedly read. Now, system controllingunit 93 detects an interrupt generated by the passer-by. At step 137, itis judged as. “Yes” and control moves to the flowcharts of FIGS. 21A and21B.

At steps 152 through 157, it is judged as “No,” and judged as “Yes” atstep 160 since the Enter key has been pressed. At step 203, PGC StandardInformation “Item Activate( )” is referred to. Since it is set as “notpermit,” control returns without any operation. After the return,post-processing command “Link PGC#55” is executed. The command storesPGC information #55 in PGC information buffer 31 and reads VOB#2 andVOB#5 according to a pre-processing command. The passer-by may besomewhat confused by this branch against his/her will, but, by askingthe staff, can learn of the mechanism of the demonstration function.Such a demonstration adequately displays the charm of the “Travel Mook”to passers-by.

As understood from the present embodiment, the management informationpacks include the PCI user operation limitation information whichspecifies “permit” or “not permit” for receiving user instructions ofspecial reproductions such as rewind. With such a construction, yes orno of special reproduction key interrupt for each image can be set witha time accuracy of about 1.0 second. This enables the prohibition ofexecuting fast forward during reproduction of an advertisement or travelagreement.

The PGC information also used as the reproduction route informationincludes the PGC user operation limitation information which specifies“permit” or “not permit” for receiving user instructions of specialreproductions such as rewind. With such a construction, execution offast forward can be prohibited in a reproduction route including abranch. That is, yes or no of execution of special reproduction can beset for each reproduction route differently regardless of what image isreproduced.

For example, if the user presses a key of a special reproduction on theremote controller to generate a key interrupt during a reproduction ofVOBs according to PGC information for 10 minutes or 20 minutes, yes orno of execution of the special reproduction is determined according tothe PGC user operation limitation information. Here, the PGC useroperation limitation information can be set not to permit the executionof fast forward and rewind. Then, the user can select and determine abranch target in an interactive operation on the DVD player, but cannotuse the fast forward and rewind functions. This prevents the user frommissing interactive operations.

For a reproduction route for sequentially reproducing VOBs which is usedin a digest version and the like, yes or no of execution of the specialreproduction is determined according to the PCI Standard Information orPGC Standard Information. That is, yes or no of execution can be set foreach special reproduction differently. Then, the user is led to operateby using only permitted functions. Therefore, it is possible to create adigest version using the special reproductions effectively.

In the present embodiment, “permit” or “not permit” is set for each ofPGC Standard Information “Upper Item Select( ),” “Lower Item Select( ),”“Right Item Select( ),” “Left Item Select( ),” and “Item Activate( ).”However, the whole specification of the above information can be set inone bit. For example, “permit” or “not permit” may be set for “ItemSelect Activate( )” instead of the above five pieces of PGC StandardInformation. If “permit” is set for the PGC information “Item SelectActivate( ),” a key interrupt is generated by pressing any of the cursorkeys and ENTER key.

In the present embodiment, a VOB unit consists of a GOP. It is needlessto say that if the stored moving pictures have a reproduction time ofabout a second, a VOB unit may consist of two or three GOPs with veryshort reproduction time. In this case, a management information pack isset before such a plurality of consecutive GOPs. The managementinformation pack is effective for the plurality of GOPs.

In the present embodiment, the digital moving picture data under MPEG2is used for the moving picture data. However, other kinds of movingpicture data such as the digital moving picture data under MPEG1 and thedigital moving picture data with a conversion algorithm other than DCT(Discrete Cosine Transform) under MPEG may be used as far as the movingpicture data can form the multimedia data with the audio data and thesub-picture data.

In the present embodiment, the management information packs are includedin VOBUs in units of GOPs, being the units of reproducing moving picturedata. However, it is needless to say that if the method for compressingdigital moving pictures changes, the unit of the management informationpack changes according to the compression method.

Now, a method for producing an optical disc used in the presentembodiment is described. The editor is supposed to prepare master tapessuch as video tapes of various shots filmed with video cameras and musictapes in which songs and sounds are recorded live. The moving picturesand sounds in the tapes are digitized and loaded into a nonlinearediting machine. The editor creates menus and items using applicationprograms such as a graphic editor loaded in the editing machine,reproducing pictures and sounds frame by frame. The editor also createsmanagement information packs having highlight commands by using a GUIgenerator and the like. Then, the editor encodes the above data underMPEG to create moving picture data, audio data, sub-picture data, andmanagement information pack. Then, the editor creates the VOB unit andVOBs by using the nonlinear editing machine. The editor assigns numbersto the VOBs. Also, the editor creates PGC information #1, #2, #3, . . ., #n, video file unit title search pointer table, and video filemanagement table. The editor loads these pieces of data into a memory ina workstation.

The data is converted into logical data sequences so that the data isrecorded in the file area. The logical data sequences are recorded intoa medium such as the magnetic tape, then converted to physical datasequences. The physical data sequences include volume data with ECC(Error Check Code), E-F conversion, data in the lead-in area andlead-out area. A master optical disc is produced by using the physicaldata sequences. Then, copies of the master optical disc are manufacturedby using a pressing machine.

Conventional CD manufacturing machines may be used for manufacturing theabove-constructed optical disc except a part of logical data sequencesrelated to the data construction of the present invention. Concerningthis point, please refer to Heitaro Nakajima and Hiroji Ogawa: CompactDisc Dokuhon, Ohmu Ltd. and Applied Physics Society Optics Meeting:Optical Disc System, Asakura Shoten.

Although the present invention has been fully described by way ofexamples with reference to the accompanying drawings, it is to be notedthat various changes and modifications will be apparent to those skilledin the art. Therefore, unless such changes and modifications depart fromthe scope of the present invention, they should be construed as beingincluded therein.

What is claimed is:
 1. An optical disc for use with a reproductionapparatus, comprising a data region for storing a plurality of videoobjects; and an index region for storing a sequence information entrywhich defines a sequence of video objects, the sequence informationentry indicating a reproduction order and positions of the video objectsincluded in the sequence, wherein the plurality of video objects includeone or more video objects that provide image data representative of aviewer option that can be exercised by a user operation during thereproduction of the video object, wherein the index region furtherstores a sequence-management information entry which indicates whetheror not a first user operation to the reproduction apparatus duringreproduction of the video objects included in the sequence isprohibited, wherein each of the video objects includes at least oneblock, and the block includes a video segment and segment-managementinformation for the video segment which indicates whether or not, duringthe display of image data representative of the viewer option, a seconduser operation is prohibited during reproduction of the video segment.2. The optical disc according to claim 1, wherein the first useroperation and the second user operation are the same user operation, andwherein said user operation is prohibited when either one of thesequence-management information entry and the segment-managementinformation indicates said user operation is prohibited.
 3. The opticaldisc according to claim 2, wherein said user operation is an instructionto perform a high-speed reproduction of video objects.
 4. The opticaldisc according to claim 2, wherein said user operation is an instructionto prohibit pausing during a reproduction of video objects.
 5. Thereproduction apparatus for the optical disc of claim 1, comprising: areading means for reading the sequence information entry and thesequence-management information entry from the optical disc; a memoryfor storing the sequence-management information entry; a user operationreceiving means for receiving the predetermined user operation; and acontroller for controlling the reading means to read the sequenceinformation entry and the sequence-management information entry from theoptical disc; for controlling the reading means to read video objectsincluded in a sequence defined by the read sequence information; fordetermining, when a user operation is received, whether or not thereceived user operation is prohibited based on the sequence-managementinformation entry; for allowing the received user operation to beperformed when the received user operation is determined not to beprohibited; and for prohibiting the received user operation from beingperformed when the received user operation is determined to beprohibited.